[Federal Register Volume 60, Number 183 (Thursday, September 21, 1995)]
[Rules and Regulations]
[Pages 49048-49083]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-22771]
[[Page 49047]]
_______________________________________________________________________
Part II
Department of Transportation
_______________________________________________________________________
Research and Special Programs Administration
_______________________________________________________________________
49 CFR Part 171, et al.
Crashworthiness Protection Requirements for Tank Cars; Detection and
Repair of Cracks, Pits, Corrosion, Lining Flaws, Thermal Protection
Flaws and Other Defects of Tank Car Tanks; Final Rule
Federal Register / Vol. 60, No. 183 / Thursday, September 21, 1995 /
Rules and Regulations
[[Page 49048]]
DEPARTMENT OF TRANSPORTATION
Research and Special Programs Administration
49 CFR Parts 171, 172, 173, 179, and 180
[Docket Nos. HM-175A and HM-201; Amdt Nos. 171-137, 172-144, 173-245,
179-50, and 180-8]
RIN 2137-AB89 and 2137-AB40
Crashworthiness Protection Requirements for Tank Cars; Detection
and Repair of Cracks, Pits, Corrosion, Lining Flaws, Thermal Protection
Flaws and Other Defects of Tank Car Tanks
AGENCY: Research and Special Programs Administration (RSPA), DOT.
ACTION: Final rule.
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SUMMARY: RSPA is amending the Hazardous Materials Regulations (HMR) to:
Require facilities that build, repair, and ensure the structural
integrity of tank cars, to develop and implement a quality assurance
program (QAP); allow the use of non-destructive testing (NDT)
techniques, in lieu of currently prescribed periodic hydrostatic
pressure tests, for fusion welded tank cars; require thickness
measurements of tank cars; allow the continued use of tank cars, with
limited reduced shell thicknesses, for certain hazardous materials;
increase the frequency for inspection and testing of tank cars for
added safety; clarify tank car pretrip inspection requirements; expand
the use of thermal protection systems and head protection on tank cars
to include certain other high hazard materials; add new requirements
for bottom-discontinuity protection; require the use of protective
coatings on insulated tank cars; prohibit the use of self-energized
manways located below the liquid level of the tank; remove
``grandfather'' provisions allowing certain uses of tank cars; and
improve the puncture resistance of tank cars used for certain high
hazard materials, including those that are poisonous-by-inhalation
(PIH) and those determined by the Environmental Protection Agency (EPA)
to pose health and environmental risks.
These actions are being taken to enhance the safe transportation of
hazardous materials in tank cars. The intended effects of these actions
are to improve the crashworthiness of tank cars and to increase the
probability of detecting critical tank car defects.
DATES: Effective date. The effective date of these amendments is July
1, 1996.
Compliance date. Voluntary compliance with the regulations, as
amended herein, is authorized November 1, 1995.
Incorporation by reference date. The incorporation by reference of
certain publications listed in these amendments is approved by the
Director of the Federal Register as of July 1, 1996.
FOR FURTHER INFORMATION CONTACT: Ed Pritchard (telephone 202-366-0509)
and James H. Rader (telephone 202-366-0510), Hazardous Materials
Division; or Thomas A. Phemister (telephone 202-366-0635), Office of
Chief Counsel, Federal Railroad Administration, 400 Seventh Street,
S.W., Washington, D.C. 20590-0001.
SUPPLEMENTARY INFORMATION:
I. Introduction
This final rule consolidates two related notices of proposed
rulemaking published under Docket HM-175A [58 FR 52574, October 8,
1993] and Docket No. HM-201 [58 FR 48485 September 16, 1993], that
address the safe performance of tank cars used to transport hazardous
materials. RSPA believes that, by consolidating these two rulemakings,
changes to sections that are affected by both rules will be more easily
understood by readers. This preamble discusses separately, for each
rulemaking, the notices of rulemaking and comments received in response
to these notices. A consolidated ``Review by Section Summary''
summarizes the changes made under this final rule.
The Federal Railroad Administration (FRA) has enforcement authority
for tank cars and rail transportation. FRA developed these rulemakings
jointly with RSPA.
II. Docket HM-175A--Crashworthiness Protection Requirements for
Tank Cars
A. Background
Based on research and on the FRA's continuing review of serious
accidents, involving the transportation of hazardous materials in tank
cars in the United States and Canada, RSPA issued a number of
regulations to improve the survivability of tank cars in
accidents.1 In these rulemakings, RSPA required the installation
of a tank-head puncture-resistance system (head protection), a coupler
vertical restraint system (shelf couplers), insulation, and a thermal
protection system for certain high-risk hazardous material ladings. The
difference between a ``thermal protection system'' and ``insulation''
is that a ``thermal protection system'' protects a tank from a pool or
torch-fire environment. In contrast, ``insulation'' protects the lading
inside the tank from ambient, temperature differentials, much like home
insulation. The record shows that these systems, working in
combination, have greatly reduced the potential harm to human health
and the environment when tank cars are involved in accidents.
\1\The discussions in the following rulemakings provide greater
detail about each of these safety system requirements: Interlocking
Couplers and Restrictions of Capacity of Tank Cars, Docket HM-38, 35
FR 14215 (September 9, 1970); Tank Car Tank Head Protection, Docket
HM-109, 41 FR 21475 (May 26, 1976); Shippers; Specifications for
Pressure Tank Cars, Docket HM-144, 42 FR 46306 (September 15, 1977);
Shippers, Specifications for Tank Cars, Docket HM-174, 49 FR 3473,
(January 27, 1984); Specifications for Railroad Tank Cars Used to
Transport Hazardous Materials, Docket HM-175, 49 FR 3468 (January
27, 1984); Transportation of Hazardous Materials, Miscellaneous
Amendments, Docket HM-166W, 54 FR 38790 (September 20, 1989); and
Performance-Oriented Packaging; Changes to Classification, Hazard
Communication, Packaging and Handling Requirements Based on UN
Standards and Agency Initiative, Docket HM-181, 55 FR 52402
(December 21, 1990).
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On October 8, 1993, RSPA published a notice of proposed rulemaking
(NPRM) under Docket HM-175A (58 FR 52574) based, in part, on
recommendations issued by the National Transportation Safety Board
(NTSB) and comments received in response to an advance notice of
proposal rulemaking published on May 15, 1990 [55 FR 20242], and a
supplemental advance notice of proposed rulemaking published on August
29, 1990 [55 FR 35327]. The NPRM solicited comments on the costs and
safety benefits that would be derived should the HMR be amended in the
following areas: (1) Tank-head protection; (2) thermal protection; (3)
self-energized manways below the tank liquid level; (4) non-pressure
tank cars for PIH materials; (5) grandfather provisions allowing use of
certain tank cars conforming to former standards; (6) bottom
discontinuity protection on tank cars; (7) protective coatings on
insulated tanks; and (8) tank cars of limited and designated
specifications, with greater protection in accidents for transporting
materials determined by EPA to pose health and environmental risks.
On January 6, 1994, FRA and RSPA held a public hearing to solicit
information to assist in deciding what actions, if any, should be taken
to improve the survivability of tank cars involved in hazardous
materials accidents. Twelve persons made presentations at the public
hearing. In addition, RSPA received 37 written comments in response to
the NPRM from representatives of trade associations and the various
industries that own, lease, transport, or use tank
[[Page 49049]]
cars. All written and oral comments were given full consideration.
B. Tank Cars Transporting ``Thermally Reactive Materials'' (Materials
That May Violently Decompose or Polymerize When Exposed to Fire)
In the NPRM, RSPA proposed to require the use of full-head
protection and thermal protection on tank cars used for certain
materials termed, ``thermally reactive.'' These materials, listed by
name, are thought by many to be capable of a violent decomposition or
polymerization reaction when exposed to fire. For these materials, the
critical temperature for the tank car, and its thermally reactive
lading, may be the heat at which the material undergoes decomposition
or polymerization--as opposed to the temperature at which the steel of
the tank becomes so plastic, it begins to lose tensile strength.
The proposal was based on several accidents involving thermally
reactive materials. For example, on August 2, 1988, at 9:00 p.m., in
Brazoria, Texas, 13 cars of a Union Pacific freight train
derailed.2 Seven of the derailed tank cars contained acetaldehyde,
and none of these tank cars had a thermal protection system, which was
not required. Two acetaldehyde tank cars sustained coupler punctures
and released their contents, which ignited. The resulting fire engulfed
four other acetaldehyde tank cars, and each of them had a total failure
or rupture of the tank shell within 5 to 10 minutes after the
derailment. Witnesses reported 3-4 explosions between 9:05 p.m. and
9:10 p.m.
\2\Union Pacific Derailment at Brazoria, Texas, FRA Accident
Investigation No. 137-88, Railroad Report No. 0888H0200, August 2,
1988.
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In another accident, NTSB found that the puncture of a tank car
containing hydrogen peroxide resulted in a release of lading and, when
the hydrogen peroxide combined with contaminants on the ground, a
chemical reaction occurred causing a fire.3 The fire heated and
ignited nearby polyethylene pellets, causing an explosion of the
hydrogen peroxide tank car and releasing a force equivalent to an
explosion of 10 tons of TNT (trinitrotoluene).
\3\Collision and Derailment of Montana Rail Link Freight Train
with Locomotive Units and Hazardous Materials Release, Helena,
Montana, February 2, 1989, National Transportation Safety Board
Report NTSB/RAR-89/05, National Transportation Safety Board,
Washington, D.C.
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Most commenters opposed the requirement for full-head protection or
thermal protection on tank cars used for thermally reactive materials.
In clarifying its comments on the NPRM, the Association of American
Railroads (AAR) stated that full-head protection is not necessary for
tank cars used for these materials, unless the materials pose another
hazard that warrants such protection. Other commenters, such as
American Petroleum Institute (API), Chemical Manufacturers Association
(CMA), and the Compressed Gas Association, Inc. (CGA), suggested that
RSPA open a new ANPRM to address these materials. A commenter stated--
the creation of this category has ramifications that reach far
beyond this particular rulemaking, which deals with one mode of
transportation (rail) and one type of packaging (tank cars). We are
concerned with the likelihood that, in the future, the Department
will expand the regulation of TRMs to affect other modes of
transportation and types of packaging.
Other commenters objected to the proposal to identify by list,
rather than by definition, certain existing hazardous materials that
would be designated ``thermally reactive.'' CMA challenged the
placement of several chemicals on the list, such as ``styrene, monomer
inhibited,'' ``vinyl toluene,'' ``vinylidene chloride,'' ``sulfur
trioxide,'' and ``hydrogen peroxide.'' CMA further stated that--
[s]tyrene, for example, is flammable and can polymerize in an
accident but solidifies causing little or no harm to the
environment. For hydrogen peroxide tank cars, the proposed rule
would create a safety hazard by requiring thermal protection.
Another commenter stated that ``[s]ome of the materials on the list
react violently when exposed to heat differentials and may decompose
with explosive force * * * Other materials, however, decompose through
polymerization into substances of relatively little hazard.'' The
commenter further explained that the key to the polymerization of
styrene is the absence of the inhibitor. Styrene is typically shipped
with inhibitor concentrations great enough to cover fairly lengthy,
unexpected delays in transportation. If a tank car of styrene is
exposed to extreme external heat, disregarding its flammable nature,
the inhibitor will dissipate rapidly as the temperature of the material
rises above 125 deg.F., which will allow the polymerization process to
begin. As a result of the polymerization, the internal heat of the
product will increase, and, with increasing temperature, the process
will accelerate.
Several commenters opposed the requirement for a thermal protection
system on tank cars used to transport ``hydrogen peroxide.'' One of the
commenters stated that hydrogen peroxide does not polymerize or burn,
and the products of decomposition--water and oxygen--are not toxic.
Two commenters, Eka Nobel and FMC Corporation (FMC), furnished
independent analyses of the fire effects on tank cars containing
``hydrogen peroxide.'' Eka Nobel contracted with the IIT Research
Institute (IITRI), which used FRA's computer model to analyze the fire
effects on a tank car containing hydrogen peroxide.4 The results
of IITRI's analysis indicate that a tank car constructed from stainless
steel will meet the thermal protection criterion for withstanding the
effects of a pool fire.
\4\``Temperatures, Pressures and Liquid Levels of Tank Cars
Engulfed in Fires,'' NTIS DOT/FRA/OR&D-84/08.11, (1984), Federal
Railroad Administration, Washington, DC.
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FMC furnished a detailed, mathematical heat transfer model using a
correlation contained in a National Fire Protection Association (NFPA)
publication, ``NFPA Pamphlet No. 30.'' FMC stated that for materials
that decompose exothermically, such as hydrogen peroxide, thermal
stability requires that the heat losses to the surroundings balance the
heat generated by the decomposition. Failure to remove the heat of
reaction could lead to runaway decomposition, and if the increased
pressure exceeds the burst pressure of the tank, the tank will fail.
Furthermore, heat input causes oxygen generation from thermal
decomposition of peroxide and vapor generation, by boiling off the
water-peroxide mixture. FMC further stated that because water is more
volatile than peroxide, the hydrogen peroxide concentration in the tank
will increase (although this may be compensated by water formation and
peroxide loss from thermal decomposition). If the peroxide
concentration reaches 74 percent by weight, the vapors in equilibrium
with the liquid (40 percent by weight of peroxide) can detonate, if
ignited, causing the tank car to fail.
The results of FMC's mathematical heat transfer model show that
tank cars containing hydrogen peroxide (having no less than a 7-percent
outage) will not fail and such tank cars will meet the thermal
protection criterion in Sec. 179.18 of this final rule for withstanding
the effects of a pool-fire. Readers who are interested in a detailed
discussion of Eka Nobel or FMC's fire studies on tank cars containing
hydrogen peroxide, should refer to the comments filed in the RSPA
Dockets Unit.
Many commenters suggested a performance-based definition as a means
to ensure the proper identification and packaging of thermally reactive
materials, because, with increasing temperature, all materials will
reach a stability limit.
[[Page 49050]]
These commenters suggested a performance-based definition that would
include the polymerization potential; the rate of the chemical reaction
(reaction kinetics); any highly exothermic reaction; the formation of
gases, vapors, or fumes in a quantity sufficient to present a danger to
human health and the environment; and any reactive by-products that
could lead to over-pressurization of the tank. Commenters stated that a
performance-based definition was the best way to ensure that the proper
packaging requirements are attached to the appropriate hazardous
materials.
As evidenced from the comments, there is no single agreement on the
best approach to identify these materials, nor to ensure the proper
packaging requirements are assigned to these materials. Because of the
multiplicity of these yet unresolved issues, the packaging requirements
proposed in the NPRM for thermally reactive materials have not been
adopted in this final rule.
C. Tank-Head Protection
In the NPRM, RSPA proposed several changes relating to tank-head
protection. The proposal would require tank-head protection on tank
cars, used for all Class 2 materials and for tank cars constructed from
aluminum or nickel plate, when used to transport a hazardous material.
RSPA included Division 2.2 in its proposal to reduce the violent
rupture hazard and the asphyxiation potential to railroad workers or
bystanders exposed to the product if these tank cars are punctured. The
proposal to require full-head protection for tank cars constructed from
aluminum or nickel plate is based on the vulnerability of the tank head
to a puncture. The top-half of the tank head is vulnerable to puncture
in a derailment. Existing tank cars with half-head protection were
excluded, based on RSPA and FRA's regulatory analysis discussed later
in this preamble. Consistent with these proposed changes, RSPA also
proposed to eliminate a grandfather provision, in place since 1984,
following publication of a final rule under Docket HM-175, that permits
certain tank cars, with a capacity of less than 70 kiloliters (kl;
18,500 gallons), to continue in service without head protection.
RSPA first introduced tank-head protection requirements after a
series of railroad accidents in the late 1960s and early 1970s
involving head punctures of tank cars (39 FR 27572 and 41 FR 21475).
The requirements of, and criteria for, head protection were based on
tests performed by FRA, the AAR, and the Railway Progress Institute
(RPI) Tank Car Safety Research and Test Project in the early 1970s. In
summary, these tests showed that head punctures, caused by over-speed
impacts in railroad classification yards, generally occurred at speeds
above 12 mph and often happened when a loaded tank car struck a
standing empty tank car, causing the empty car to ``jump'' and ram its
coupler into the head of the oncoming tank. A recent informal staff
analysis of data on main-line accidents showed that objects, such as
broken rails and couplers, may penetrate the top half of the tank head,
indicating that head protection is essential, even though not 100
percent effective, in a train derailment.
The NPRM referenced the recent FRA research on puncture resistance,
which shows that puncture resistance is strongly influenced by impact
location, head and jacket thickness, and insulation thickness.5
Stated differently, research demonstrates that puncture resistance is
an inter-related function of head thickness, insulation thickness, and
jacket thickness, and that the concept of ``head protection'' must
include more than just traditional ``head shields.'' Based on the
results of this research, FRA expects that certain tank cars may meet
the 29 kilometers per hour (18-mph) threshold for puncture-resistance,
prescribed in Sec. 179.16 of this final rule, without further
modification.
\5\Coltman, M., & Hazel, M., Jr., Chlorine Tank Car Puncture
Resistance Evaluation (1992), Federal Railroad Administration,
Washington, DC (NTIS DOT/FRA/ORD-92/11).
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Tank cars currently equipped with half-head protection. Most
commenters agreed that there is no need to require full-head protection
on existing tank cars having only half-head protection.
In comments filed in this docket, NTSB stated that the NPRM
addressed many of their concerns, but noted the proposal failed to
require existing tank cars used to transport Division 2.1 (flammable
gas) materials, or other materials with extreme hazards, to be modified
with full-head protection. Thus, these materials could be transported
indefinitely in tank cars without full-head protection modifications.
While we appreciate the concerns of NTSB, we are not able to
establish a positive benefit/cost ratio by requiring modification of
the existing tank car fleet, primarily because the half-head protection
on existing cars is already about 95-percent effective. It is not
credible to argue that greater safety gains are realized by mandating
safety improvements on tank cars that currently have a 95-percent
effective protection system, than by requiring improvements on tank
cars without a head-protection system. The regulatory evaluation
considered both approaches, with emphasis being placed on choosing the
alternative offering maximum potential benefit to society, while
imposing the least net cost. Based on the regulatory evaluation, this
final rule does not require that existing half-head protection be
removed and replaced with full-head protection.
Head protection systems for existing tank cars with capacities less
than 70 kl (18,500 gallons). RSPA received diverse comments in response
to this proposal in the NPRM. One commenter agreed that class DOT 105
tank cars having capacities less than 70 kl (18,500 gallons) and
transporting Division 2.1, 2.2, and 2.3 materials, should have full-
head protection, unless already equipped with half-head protection.
CMA supported the proposal to require full-head protection on newly
built class DOT 105A tank cars, regardless of tank capacity, when used
to transport a Division 2.1 or 2.3 material. The Reebie Associates
report, submitted as part of CMA's comments, assumed that all tank cars
would require head protection, except those that have a tank test
pressure of 41.4 Bar (600 pounds per square inch [psi]).
The Chlorine Institute agreed that head protection systems are now
warranted for the transportation of chlorine, but recognized, based on
FRA research and the accident history, that many tank cars currently
used to transport chlorine meet the performance standard by virtue of a
thick tank-head and a tank jacket.
NTSB commented that RSPA should require tank-head protection,
within 5 years, for all class 105 tank cars having capacities of less
than 70 kl (18,500 gallons) when used to transport a Division 2.1
(flammable gas) material as proposed in Option B of the NPRM.
RPI commented that, except for the nominal 41 kl (11,000-gallon)
capacity tank cars, existing tank cars of less than 70 kl (18,500-
gallon) capacity, transporting Division 2.1 materials or anhydrous
ammonia, should have head-protection, but only half-head protection.
RPI further commented that RSPA should exclude tank cars having a
nominal capacity of 41 kl (11,000 gallons) from any head protection
modification program, because most tank cars in this category are near
or exceed 30 years of age; consequently, the economic life of the tank
is nearing an end.
RSPA and FRA believe that there is no longer a justification for
excluding tank cars having a capacity less than 70
[[Page 49051]]
kl (18,500 gallons) from the modification requirements. While CMA's
report is not so optimistic on the use of DOT 105A500W specification
tank cars, RSPA and FRA believe that most of these tank cars will meet
the performance standard by virtue of their increased head thickness,
insulation, and metal jacket. Because of the small number of tank cars
in this category, and the small incremental cost to make such head
protection modifications for those tank cars that do not otherwise meet
the performance standard mandated by this rule, in this final rule RSPA
is removing the 70 kl (18,500-gallon) exception for existing tank cars
in current Secs. 173.314(c) and 173.323(c)(1).
Further, while most commenters supported the 10-year modification
program for existing tank cars, we agree with NTSB, that when these
tank cars are used to transport Division 2.1 materials, a 5-year
modification program (as proposed in Option B of the NPRM) will ensure
that those cars presenting the greatest risk are modified first.
Tank cars transporting materials in Division 2.2. A commenter
stated that the proposal to require full-head protection for Division
2.2 gases is sound and should be finalized. Several other commenters
disagreed with the proposal to require full-head protection for
Division 2.2 materials. The Reebie Associates report, submitted by CMA,
identified 467 Class 2 materials affected by the proposed rule, 11 of
which are Division 2.2 materials. The report shows that shippers used
1,448 tank cars in 1992 to transport these Division 2.2 materials, as
follows:
------------------------------------------------------------------------
Commodity Population
------------------------------------------------------------------------
Argon, refrigerated liquid................................ 2
Ammonia solutions......................................... 28
Bromotrifluoromethane..................................... 1
Carbon dioxide, refrigerated liquid....................... 1,016
Chlorodifluoromethane..................................... 145
Chlorotetrafluoroethane................................... 26
Chloropentafluoroethane................................... 37
Dichlorotetrafluoroethane................................. 164
Fertilizer, ammoniating solutions......................... 4
Trifluoromethane.......................................... 1
Xenon, refrigerated liquid................................ 24
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Total................................................. 1,448
------------------------------------------------------------------------
CGA opposed the full-head protection requirement for tank cars
transporting carbon dioxide. CGA referenced the testimony presented by
RPI at the January 6, 1994 public hearing concerning recent head impact
tests that verified the adequacy of the current head protection system
on DOT 105A500W specification tank cars.
With regard to CMA's and CGA's comments, RSPA and FRA believe that
most tank cars used for ``carbon dioxide, refrigerated liquid,'' meet
the performance standard for head protection by virtue of their tank
head thickness and metal jacket. Tank cars used for ``argon,
refrigerated liquid,'' and ``xenon, refrigerated liquid,'' also meet
the head performance standard by virtue of the authorized class DOT 113
tank car specification. These tank cars must have a minimum outer
jacket tank head of not less than \1/2\-inch thick steel. See
Sec. 179.400-8(d). A total of 1,042 tank cars, or 72 percent of the
total Division 2.2 tank car population, are used to transport these
three commodities.
A commenter opposed tank-head protection for Division 2.2 materials
stating, ``heavy walled tank and protective housing for the fittings is
adequate for the transportation environment.'' The commenter also
provided an in-house report using a computer model that claims the
asphyxiation potential from a punctured Division 2.2 refrigerant gas
tank car to be very low.'' Another commenter opposed applying head
protection to tank cars transporting Division 2.2 refrigerant gases.
This commenter stated that, in the past, DOT had judged a material
based on its hazards under normal conditions of transport, and that in
this rulemaking, DOT was over-assessing the potential for harm in a
low-probability event. RPI supported full-head protection on new,
insulated tank cars transporting Class 2 materials, but it opposed
full-head protection for new non-insulated tank cars or for existing
tank cars transporting these materials.
We believe that even though the probability of an event occurring
with these materials is low, safety concerns still need to be
addressed, because the event may lead to high consequences, such as a
large scale evacuation or an oxygen deficient atmosphere in a
concentrated populated area. Taking the safety steps adopted in this
final rule will mitigate these hazards.
We also believe that the transportation risks associated with
Division 2.2 gases are sufficient to require full-head protection for
new tank cars, and for existing tank cars without head protection, when
used to transport Division 2.2 materials. As noted above, this rule
does not require existing tank cars equipped with half-head protection
to be modified with full-head protection. RSPA and FRA are aware of
industry concerns that the attachment of full-head protection to non-
jacketed cars is a feature not yet proven by long service. Similar
arguments were raised when head protection was first required almost
two decades ago [HM-144; 42 FR 46306, September 15, 1977]. FRA is aware
of companies with plans to attach full-head protection to their non-
jacketed tank cars. As discussed later in this preamble, a phased-in
10-year modification program is provided for existing tank cars.
Existing tank cars without head protection. Most commenters to the
NPRM supported the need to modify existing tank cars to meet the
current safety requirements. One commenter supported the need to modify
existing tank cars constructed from aluminum plate with half-head
protection, but believed full-head protection should be required when a
proven full-head shield design is available. Another commenter
suggested that DOT should specifically recognize that tank cars used in
``chlorine'' service meet the performance requirements for head
protection and that DOT should not require any additional head
protection for these tank cars.
As stated in the NPRM, the benefits of head protection are real,
predictable, and quantifiable. RSPA disagrees with commenters who state
that full-head protection is not warranted. Where earlier rules
required head protection on tank cars, it was a matter of recognizing
the highest priority needs first. The question is not one of demanding
low-priority, safety benefits, but the need to expand the safety base
of hazardous materials transportation in tank cars. Further, the small
additional cost of installing full-head protection on cars that now
have no head protection system, as compared with adding only half-head
protection, is justified on the basis of increased safety (see Chapter
V of the Economic Impact Assessment and Regulatory Flexibility
Analysis). In this final rule, RSPA requires existing tank cars that
currently have no head protection, to have full-head protection
installed when used to transport a Class 2 material. As explained
below, RSPA is also requiring full-head protection for tank cars
constructed from aluminum or nickel plate when used to transport
hazardous material.
Tank cars constructed from aluminum and from nickel plate.
Commenters supported the need for head protection on tank cars
constructed from aluminum or nickel plate, but not the full-head
protection requirement proposed in the NPRM. Most commenters stated
that there is no design available for the securement of full-head
protection on tank cars without metal jackets.
[[Page 49052]]
One commenter stated that his company's new aluminum tank cars,
constructed with greater tank shell and head dimensions than standard
tank cars, offer greater protection without head protection. The
commenter stated that further testing should be done and suggested that
RSPA and FRA submit more evidence to support the need for this
requirement.
CMA supported requiring half-head protection for new tank cars
constructed from aluminum or nickel plate, and requiring half-head
protection for existing tank cars for certain hazardous materials.
Several commenters requested that RSPA consider the characteristics of
an individual Division 2.2 material, and that materials not subject to
the HMR, and low hazard materials should be excluded.
We realize that the use of good engineering practice and design
specifications are needed to secure full-head protection to tank cars
without metal jackets. Although there is no service experience for a
full-head protection design on non-insulated tank cars, such designs
are certainly not unreachable within the years ahead. In rulemaking
proceedings under another docket [HM-144; 42 FR 46306, September 15,
1977] introducing half-head protection, commenters offered similar
arguments regarding head protection, for which solutions were later
found as a result of technological innovation. Currently, FRA is aware
of several companies that are nearing completion on their full-head
protection designs for aluminum and nickel tank cars. We, therefore,
believe that the introduction of this requirement will not adversely
affect industry. In this final rule, the use of full-head protection
for all tank cars constructed from aluminum or nickel plate is required
when used to transport a hazardous material. As discussed later in this
preamble, RSPA has provided for a phased-in 10-year modification
program.
D. Thermal Protection Systems
In the NPRM, RSPA proposed to require a thermal protection system
for a Class 2 material when a thermal analysis of the tank car and
lading shows that a release will occur other than through the safety
relief valve when the tank car is subjected to either a 100-minute pool
fire or a 30-minute torch fire. The current HMR require thermal
protection for Division 2.1 (flammable gas) materials (with limited car
capacity restrictions) and certain Division 2.3 (poison gas) materials.
RSPA proposed to expand the thermal protection requirements to include
Division 2.2 materials because, as stated by AAR, ``[a]t a chemical
accident, there are generally two reasons for an evacuation, one is to
protect the public from any toxic, poisonous, or noxious vapors or
fumes generated by the product itself . . ., the second is to protect
the public from thermal ruptures and the container debris that may be
hurled from an incident site'' [Emergency Action Guides, p. VII]. RSPA
also proposed to expand the thermal protection requirement to include
all Division 2.3 materials.
RSPA began to require the application of a thermal protection
system on tank cars transporting Division 2.1 materials (flammable
gases) or ``ethylene oxide'' (Division 2.3) after a series of major
railroad accidents involving fires and ruptures of non-insulated
pressure tank cars. The design of and criteria for thermal protection
systems were based on tests performed by FRA at the U.S. Army
Ballistics Research Laboratory in White Sands, New Mexico, and at the
Transportation Test Center in Pueblo, Colorado. These tests revealed
that a 127.2 kl (33,600 gallon) non-protected tank car filled with
propane (Division 2.1) will rupture, with 40 percent of the lading
remaining in the tank car, within 24 minutes after exposure to a pool-
fire. Rupture occurs when the residual strength of the tank shell falls
below the force generated by the vapor pressure of the lading exerted
on the inside surface of the tank shell. Further testing by FRA
demonstrated that a tank car filled with propane and equipped with a
thermal protection system delayed the thermal rupture of the tank car
for 94.5 minutes, by maintaining the shell temperature low enough to
vent 98 percent of the lading through the safety relief valve. The
current performance standard, requiring exposure to a 100-minute pool
fire and a 30-minute torch fire, was chosen because it provides
emergency response personnel time to assess the accident and to
initiate remedial actions, such as evacuating an area.
Division 2.1 (flammable gas) and 2.3 (poisonous gas) materials:
Several commenters supported the need for a thermal protection system
on tank cars transporting Division 2.1 or 2.3 materials, regardless of
tank car capacity. The AAR and another commenter supported a thermal
protection system for all Class 2 materials, unless a shipper could
show that a release will not occur, other than through the safety
relief valve, when the tank and lading are subject to a fire. RPI also
concurred on the need for thermal protection for all Class 2 materials,
but, except for Division 2.1, but did not support the high-temperature
performance standard proposed in Sec. 179.18. RPI stated that most
insulation materials (e.g., 4 inches of glass-fiber insulation) are
adequate.
In this regard, RSPA stated in the NPRM that many insulation
materials also provide good thermal protection. These insulation
materials, when analyzed with the tank and the lading, may show that
nothing further needs to be installed on the tank car to achieve
passage of the pool- and torch-fire performance tests. Research
sponsored by FRA on urethane-foam and glass-fiber insulation systems
show that urethane-foam insulation will pass the pool- and torch-fire
requirements and that glass-fiber insulation will also pass both tests,
provided the insulation is held in place with a plastic or wire scrim.
Owners of tank cars with either of these systems, or another comparable
system, may find that their thermal analysis of the tank car shows the
presence of sufficient thermal protection to meet the performance
standard. In this case, the tank car owner would have to verify only
that the insulation material installed on the tank car is capable of
passing the pool- and torch-fire verification or ``proof'' tests in
Appendix B to Part 179 of this final rule. Owners may find that a tank
car will pass the performance standard with only minor modifications,
such as applying a thermal protection system to the manway nozzle.
Also in the NPRM, RSPA stated that, in 1981, a joint effort between
the Chlorine Institute and RPI-AAR Tank Car Safety Research and Test
Project resulted in the development of an insulation system to protect
a chlorine tank car involved in a fire. The insulation system developed
maintains back plate (inside surface of the tank car shell)
temperatures below 250.56 deg.C (483 deg.F). After reviewing the
thermal resistance capabilities of the insulation system used on
chlorine tank cars, RSPA incorporated it into the HMR in 1987. Readers
should refer for more information to Docket HM-166U, entitled
``Transportation of Hazardous Materials; Miscellaneous Amendments'', 52
FR 13034, (April 20, 1987).
Division 2.2 (nonflammable gas) materials. As noted earlier in the
preamble discussion on tank-head protection for Division 2.2 materials,
CMA commented that there were 1,448 tank cars allocated to Division 2.2
materials that had not already been captured in another service, such
as PIH. Of those, ``argon, refrigerated liquid,'' ``carbon dioxide,
refrigerated liquid,'' and ``xenon, refrigerated liquid,'' represent
1,042 tank cars, or 72 percent. CMA further commented that
[[Page 49053]]
almost 100 percent of the total would need retrofitting and that the
overall economic impact of the new regulations on this group of tank
cars amounts to $26.0 million for retrofitting and $2.59 million for
higher lease rates and additional cars in the tenth year of the
implementation period.
With regard to the issues raised by CMA, this final rule does not
contain any new thermal protection requirements for ``argon,
refrigerated liquid,'' ``carbon dioxide, refrigerated liquid,'' or
``xenon, refrigerated liquid.'' Carbon dioxide is transported in DOT
105A500W tank cars equipped with two regulator valves, a reclosing
pressure-relief device, a frangible disc, and an insulation system with
good thermal performance (a thermal conductance of 0.03 British Thermal
Units [B.t.u.] per square foot per degree Fahrenheit differential).
Consequently, existing and new tank cars in carbon dioxide service have
sufficient thermal resistance when exposed to fire. Likewise, because
with argon and xenon, refrigerated liquids are packaged under the
exceptions for atmospheric gases in Sec. 173.320, this final rule does
not impose any new thermal protection requirements. This section
exempts cryogenic atmospheric gases from the packaging requirements
when the packagings are designed to maintain pressures below 1.74 Bar
(25.3 psi) under ambient temperature conditions.
Another commenter opposed the use of thermal protection for
Division 2.2 materials on the basis that the hazards they pose do not
equate to those of Division 2.1 and 2.3 materials. The commenter
further stated that the thermal protection requirements proposed for
Division 2.2 materials do not appear to be justified by the hazards
posed, because, in many cases, these materials dissipate naturally with
little risk to the surroundings.
A commenter, primarily addressing refrigerant gases, noted that an
analysis of each Division 2.2 material, to predict the behavior of a
tank car in a 100-minute pool-fire, seemed an unnecessary precaution
because the calculations, required by the current regulations, for
sizing safety relief valves accomplish the same purpose and meet this
same standard. RSPA and FRA disagree with this commenter's position
that the current regulations for sizing safety relief valves accomplish
the same purpose as the proposed Division 2.2 thermal protection
performance standard. The current safety relief valve-sizing
requirements make several assumptions. First, the valve sizing formula
assumes the exposure factor, that portion of the tank car exposed to
fire (represented as A0.82), is about one-fourth of the tank. The
pool-fire computer model in this final rule assumes total engulfment.
Second, the safety relief valve sizing formula assumes that flame
temperatures will reach approximately 650 deg.C (1,200 deg.F.). The
pool-fire standard assumes flame temperatures will reach 871 deg.C
(1,600 deg.F) for a pool-fire and 1,204 deg.C (2,200 deg.F) for a
torch fire at 40 miles per hour.6 Third, the safety relief valve-
sizing formula does not take into consideration either an overturned
tank car venting liquid or a liquid-gas mixture (two phase flow) or the
diminished burst strength of the heated tank shell in the non-wetted
area, after prolonged fire exposure.
\6\The pool-fire computer model assumes an average heat flux
over the entire tank surface, equivalent to complete engulfment in a
fire, where the flame temperature is 815.5 deg.C (1,500 deg.F). If
a higher or lower flame temperature were assumed, the parametric
analyses in the computer model would not match the actual field test
data.
---------------------------------------------------------------------------
The Fertilizer Institute did not support the requirement for
thermal protection on tank cars transporting ``anhydrous ammonia''. It
stated that the likelihood of a fire-induced rupture of a tank car
carrying anhydrous ammonia has significantly decreased since 1980
because of added safety devices, safer placement in trains, and
improved emergency response procedures. Thus, there is little, if any,
increase to public safety by imposition of the proposed thermal
protection requirements on these tank cars.
While RSPA and FRA agree with The Fertilizer Institute that the
safety record for tank cars transporting ``anhydrous ammonia'' is good,
these cars have a potential for violent rupture similar to compressed
gas tank cars, which received thermal protection many years ago. As The
Fertilizer Institute notes, the threat of a fire-induced violent
rupture of an anhydrous ammonia tank car is more than just a
theoretical potential. Since 1990, according to figures from the AAR,
``anhydrous ammonia'' has been the sixth highest volume hazardous
material transported by railroad.
AAR and two other commenters supported the need for thermal
protection for Class 2 materials, including Division 2.2. One of these
commenters stated: ``thermal protection systems are a good, simple idea
whose time has come. The purpose of the system is to prevent rupture of
the tank car in a fire with the release of its hazardous materials
contents to the environment. Uncontrolled release of almost any
hazardous material to the environment is objectionable whether due to
toxicity, flammability, or simply clean-up costs.'' This commenter
further stated that there can be little basis for exempting anhydrous
ammonia from the thermal protection requirements simply because it is
not likely to catch fire once released. Its PIH characteristic remains,
and the potential for rupturing in a non-insulated tank car is high.
Although not all commenters agree on the need for thermal
protection for Division 2.2 materials, in this final rule RSPA requires
such a system if, after an analysis of the effects of a 100-minute pool
fire and a 30-minute torch fire, there will be a release of the tank
car lading other than through the safety relief valve. Because tank
cars may transport different ladings, and because changing ladings may
affect the whole system, owners or shippers may choose to perform a
``worst case'' analysis based on all the commodities the car is likely
to carry.7
\7\Owners are reminded that 49 CFR 173.31(a)(4) limits the use
of tank cars to those commodities for which they are authorized.
Authorized (or approved) commodities are those listed on the
certificate of construction or an AAR R-1 form. (See the AAR
Specifications for Tank Cars Section 1.4.3.1 and Appendix R, Section
R4.04.)
---------------------------------------------------------------------------
Based on these comments and FRA's research, this final rule
requires the owner or the shipper of a Class 2 material, with the
exception of ``carbon dioxide, refrigerated liquid,'' ``chlorine,'' and
``nitrous oxide, refrigerated liquid'' as explained above, to perform
an analysis of the characteristics of the material and of the thermal
resistance capabilities of the tank car, taking into consideration the
safety relief valve start-to-discharge pressure setting and relief
capacity and all areas of the tank car that are not afforded protection
from fire (such as stub sills, bolsters, and protective housings).
Tank cars constructed from aluminum and nickel plate. Most
commenters said that the lading within a tank car constructed from
aluminum or nickel plate should determine the need for a thermal
protection system.
We agree. The NPRM proposed to require a thermal protection
analysis for aluminum and nickel plate cars carrying Class 2 materials.
Based on the comments received, we believe that all such tank cars will
need protection and that such protection is essential.
This final rule requires the owner of an aluminum or nickel plate
tank car used to transport a Class 2 material to perform an analysis of
the tank car in a 100-minute pool fire and in a 30-minute torch fire
using FRA's Tank Car Fire model. If the analysis shows that a release
of the lading from the tank car,
[[Page 49054]]
will occur, other than through the safety relief valve, a thermal
protection system will be required. This final rule adopts a 10-year
phase-in period for those existing tank cars required to have thermal
protection.
E. Shell Protection
For tank cars transporting of a material poisonous by inhalation
(PIH), RSPA proposed that they have ``shell protection conforming to
Sec. 179.100-4.'' That is, the optional use of an insulated DOT 105S
tank car or a non-insulated, but thermally protected, DOT 112J or 114J
tank car having a metal jacket. Although RSPA used the term ``shell
protection'' to identify these systems, the intent of the NPRM was to
require tank cars transporting a PIH gas (Division 2.3) to conform to
the same requirements as tank cars transporting a PIH liquid. For a
complete discussion, see Performance-Oriented Packaging Standards;
Miscellaneous Amendments, Docket HM-181F, 58 FR 50224 (September 24,
1993). In the final rule issued under that docket, RSPA authorized the
optional use of an insulated DOT 105S tank car or a non-insulated, but
thermally protected, DOT 112J or 114J tank car for poisonous liquids
having a PIH hazard.
In its comments to the NPRM, one commenter supported the need for
shell protection for PIH materials. Another commenter suggested that,
in lieu of a metal jacket, RSPA should establish a performance
standard, as with thermal and head protection. Until a performance
standard is established, shell-protection resistance should be
equivalent to a tank car having a tank test pressure of 20.7 Bar (300
psi) constructed from carbon steel and with a 1/8-inch carbon steel
jacket. The commenter stated that the shell-puncture resistance should
be based on either a total metal thickness, or an approved calculation.
We agree with this commenter that a performance-based standard for
shell-puncture resistance may have merit over specification-based
standard adopted in this final rule. However, such performance based
standards have not been proposed.
Another commenter opposed the use of a metal jacket on pressure
tank cars transporting a PIH material on the basis that the FRA's
proposal did not support the conclusion that jacketing improves
puncture resistance. The commenter further questioned the use of a tank
jacket over thicker tank shells, since ``jackets provide thermal not
puncture protection.''
In response to similar remarks, RSPA discussed in the NPRM a 1987
RPI report on the vulnerability of pressure tank car shells to
puncture.8 RPI found that shelf couplers, hardboard insulation
(cork), increased shell thickness, thermal protection, small tank car
size and increased jacket thickness proved effective towards reducing
the frequency of shell punctures. The RPI report summarizes a 20\1/2\-
year history of accident data on shell punctures of pressure tank cars
and concludes that the 11-gauge steel jacket provides a measure of
shell protection. In addition to RPI's report, FRA also found, in a
research contract awarded to the AAR, that puncture resistance is
strongly influenced by impact location, by head and jacket thickness
and by insulation thickness.9
\8\Phillips, E.A., Review of Pressure Car Shell Puncture
Vulnerability, RA-09-6-52, (1987), AAR-RPI Railway Tank Car Safety
Research and Test Project, AAR Technical Center, Chicago, Illinois.
\9\[Coltman, M., & Hazel, M., Jr., Chlorine Tank Car Puncture
Resistance Evaluation, (1992) Federal Railroad Administration,
Washington, D.C. (NTIS DOT/FRA/ORD-92/11).
---------------------------------------------------------------------------
RSPA explained earlier, in Docket HM-181, that the purpose of a
metal jacket is to provide ``both accident damage and fire protection''
for certain [liquid] PIH materials.10 This final rule expands that
philosophy to all PIH materials [including compressed gases] and
authorizes the use of an insulated class DOT 105S tank car or a non-
insulated, but thermally protected, class DOT 112J or 114J tank car.
\10\See the final rule on Performance-Oriented Packaging
Standards; Miscellaneous Amendments, Docket HM-181F, 58 FR 50224
(September 24, 1993), and the NPRM, 58 FR 37612 (July 12, 1993).
---------------------------------------------------------------------------
F. Self-Energized Manways Located Below the Liquid Level of the Lading
RSPA proposed in the NPRM to prohibit the use on tank cars of a
self-energized manway located below the liquid level of the lading. The
proposal was based on a September 8, 1987 railroad yard incident in New
Orleans, Louisiana.11 In this incident, a tank car equipped with a
self-energized bottom manway and loaded with butadiene developed a leak
and caught fire. At one point during the incident, the flames were
large enough that both spans of a bridge on Interstate 10 were
engulfed. After the investigation, NTSB concluded that ``it is unlikely
that a hazardous material leak through a bottom manway during
transportation could be stopped.'' NTSB urged FRA to prohibit the
transportation of tank cars that have a manway opening located below
the liquid level of the lading in hazardous materials service. Because
the design of bottom manways depends in part on the weight of the
product and the pressure in the tank to make the seal fully effective,
this type of closure system becomes vulnerable to releasing product
when the lading is displaced within the tank. Therefore, we agree with
NTSB's conclusion.
\11\Butadiene Release and Fire from GATX 55996 at the CSX
Terminal Junction Interchange, New Orleans, Louisiana, September 8,
1987, National Transportation Safety Board Report NTSB/HZM-88/01,
National Transportation Safety Board, Washington, D.C.
---------------------------------------------------------------------------
In its comments to the NPRM, the AAR, RPI, and several other
commenters supported the proposal to remove self-energized manways
located below the liquid level of the lading. A commenter stated that
their design incorporates an externally elliptically shaped ring clamp
which is bolted to the manway closure plate with numerous closely-
spaced studs around the circumference of the ring. This commenter holds
two DOT exemptions (DOT-E 5493 and DOT-E 6117) to operate tanks cars in
hydrogen sulphide service with this design. RSPA and FRA believe that
this design is certainly preferable to that used on the car that leaked
and burned in New Orleans and is similar to a more conventional
external flange, however, we believe this design still remains a
potential source of leaks since it is located below the liquid level of
the lading. Based on these reasons, RSPA will grant the exemption
holder a reasonable amount of time to phase out the use of these tank
cars.
While some commenters agreed with a 2-year phase out program of
self-energized manways, NTSB stated that RSPA should immediately
prohibit such manways, and the AAR suggested a one-year phase-out
program.
Based on these comments, this final rule prohibits the construction
of new tank cars having an internal self-energized manway located below
the liquid level of the lading. This prohibition is added in
Sec. 179.103-5. Based on NTSB's comments, compliance with this
provision is required beginning on the effective date of this final
rule.
G. Non-Pressure Tank Cars for Materials Poisonous by Inhalation
In the NPRM, RSPA proposed to prohibit the use of non-pressure tank
cars (e.g., class DOT 111A) for materials poisonous by inhalation.
In a recent research report, FRA found that, in a single-car
national risk profile, the transportation of ethylene oxide in a DOT
111A100W4 tank car involves significantly greater risk than
transportation of the same material in a
[[Page 49055]]
DOT 105J500W tank car.12 Characteristics and parameters evaluated
in this assessment included the toxicity, fire hazard, and explosion
hazard. In comments to the ANPRM, RPI reported that, during the time
period of 1965 through 1986, class DOT 111A tank cars involved in
accidents and damaged were slightly more than three times as likely to
lose lading as were class DOT 105 cars in similar situations.13
\12\Raj, P.K., and Turner, C.K., Hazardous Materials
Transportation In Tank Cars/Analysis of Risks--Part 1, NTIS DOT/FRA/
ORD-92/34, (1993), Federal Railroad Administration, Washington D.C.
\13\Phillips, E.A., Analysis of Tank Cars Damaged in Accidents
1965 through 1986, RA-02-6-55, (1989), AAR-RPI Railway Tank Car
Safety Test and Research Project, AAR Technical Center, Chicago,
Illinois.
---------------------------------------------------------------------------
The Raj/Turner report amply demonstrates (and AAR/RPI Tank Car
Safety Test and Research Project data support) that it is
``improbable'' to assume that any single tank car (e.g., DOT 111A or
DOT 105) would be involved in an accident. However, based on FRA
accident data referenced earlier regarding DOT 111A and DOT 105 tank
cars, a significant number of such cars will be involved in accidents
during their service life.
Several commenters supported disallowing the use of non-pressure
tank cars for the transportation of PIH materials. Because of the
hazards associated with PIH materials and the performance superiority
of the so-called ``pressure'' tank cars for this service, RSPA agrees
with the commenters. This final rule removes the class DOT 111A tank
car as an authorized packaging for Division 2.3 materials on the
effective date of this final rule.
H. Phasing Out of Various ``Grandfather'' Provisions
In the NPRM, RSPA proposed to remove from the HMR several
grandfather provisions that affect tank cars. The grandfather
provisions allow tank cars built before a certain date to remain in
service without modification. As an example, in Sec. 173.314(c), Notes
23 and 24 allow the continued use of class DOT 105A tank cars for
certain compressed and flammable gases if they were built before
September 1, 1981, while tank cars built after that date must meet a
more stringent class DOT 105S or 105J standard.
NTSB stated, in a March 1, 1988 letter to RSPA, that tank cars
failing to meet current minimum safety requirements should no longer be
used for transportation of hazardous material under grandfather
provisions. NTSB stated that these grandfather provision could result
in a reduced level of safety. The AAR also petitioned RSPA to amend
Sec. 173.314(c) Note 30 (P-1138), stating that it does not provide any
assurance that tank cars with head protection will be used for PIH gas
service in the foreseeable future because companies will be able to use
tank cars without head protection for PIH compressed gas service for
the next 30 years. Other commenters agreed that the grandfather
provisions proposed for removal in the NPRM are no longer compatible
with the needs of safety.
Based on these comments, RSPA is removing certain grandfather
provisions. In Sec. 171.102, special provision ``B63'' is removed to
disallow the use of DOT 105A100W, 111A100W4, 112A200W, and 114A340W
tank cars for ``ethyl chloride'' and ``ethyl methyl ether.'' Prior to
the issuance of Docket HM-181, these two materials were classed as
flammable liquids. Because these tank cars do not have head protection
or thermal protection systems, they do not provide an equivalent level
of safety compared to other tank cars used for Division 2.1 materials.
Also, special provision ``B63'' is removed from column 7 of the
Sec. 172.101 table entries for these two hazardous materials, thereby
prohibiting the use of non-protected tank cars.
Other changes are made to disallow the use of class DOT 111A non-
pressure tank cars for Class 2 (compressed gas) materials, such as
``ammonia solutions,'' ``ethylamine,'' ``ethyl chloride,'' and ``ethyl
methyl ether.'' This final rule also removes the DOT 111A100W4 car as a
packaging for ``ethylene oxide'' in Sec. 173.323(c)(1).
I. Bottom-Discontinuity Protection for Bottom Outlets
In the NPRM, RSPA proposed to require bottom-discontinuity
protection (e.g., for bottom outlets) on tank cars. The proposed
requirements were intended to simply adopt the requirements published
by the AAR. In July of 1979, the AAR required bottom-discontinuity
protection for new tank car construction. Over a period of years, these
requirements were extended to existing tank cars on a priority schedule
determined by the nature of the commodity transported. The AAR's
program for bottom-discontinuity protection consists of either a metal
``skid'' protecting the portion of the bottom outlet that protrudes
beyond the shell or the machining of a ``breakage groove'' in the valve
assembly.
AAR, the Chlorine Institute, CMA, and several other commenters
supported the adoption of bottom-discontinuity protection for tank
cars, provided such protection was consistent with the AAR
requirements. API asked RSPA to clarify the requirements for bottom-
discontinuity protection in this final rule. API and several other
commenters stated that the proposed rule would require the modification
of a number of tank cars, built before July 1, 1979, because most were
modified according to Appendix Y and not paragraphs E9.00 or E10.00 of
the AAR Specifications for Tank Cars. Appendix Y permits three levels
of protection for allowing the types of discontinuity: bottom outlets
that extend 1 inch or more; blind flanges and washouts that extend 2
and \5/8\ inches or more; and sumps and internally closed washouts that
extend 5 inches or more. Paragraphs E9.00 and E10.00 generally require
the protection of each valve and fitting from mechanical damage by the
tank, an another protective device, or the underframe.
Several other commenters stated that the proposed rule would also
require the modification of all existing tank cars, including those
that do not transport hazardous materials. The Sulphur Institute and
another commenter opposed the need to add bottom-discontinuity
protection to existing tank cars that transport sulfur, molten,
claiming that such protection has little practical benefit.
In the public hearing held on January 6, 1994, in Washington, D.C.,
FRA stated that it was not the Department's intention to require the
modification of previously modified tank cars, nor to require bottom-
discontinuity protection for tank cars that transport materials not
subject to the HMR.
In this final rule, RSPA requires bottom-outlet protection that
conforms to paragraphs E9.00 and E10.00 of the AAR Specifications for
Tank Cars, M-1002, for all new tank cars equipped with bottom unloading
devices. Existing tank cars, without bottom-discontinuity protection,
used for the transportation of hazardous materials must conform to the
above paragraphs no later than 10 years after the effective date of
this final rule. Existing tank cars that conform to the bottom-
discontinuity protection requirements of Appendix Y of the AAR
Specifications for Tank Cars, M-1002 may continue in use after the
effective date of this final rule. This final rule does not require the
modification of existing tank cars that transport materials not subject
to the HMR.
J. Protective Coatings on Insulated Tank Cars
In the NPRM, RSPA proposed use of protective coatings on the
exterior of a
[[Page 49056]]
tank car and the interior of a tank car jacket to retard rust or
corrosion. The proposal was in response to an AAR petition (P-1050) and
FRA's findings of severe corrosion or pitting on the outer surface of
the tank shell, or the inner surface of the tank jacket, of insulated
tank cars. It is not known whether the corrosion stems from the
physical properties of the insulation itself or whether the corrosion
develops when insulation becomes impregnated or contaminated with water
or a chemical from the atmosphere in which the tank car operates.
Research within the industry has led to the development of protective
coating materials.
Most commenters supported the proposal. One commenter stated that
acid-resistant protective coatings should be applied. The commenter
further stated that several manufacturing and repair shops are using
non-acid resistant latex coatings under polyurethane-foam insulations.
Another commenter suggested that the rule should be clarified to
exclude tanks or jackets manufactured with self-protective materials
such as stainless steel. Still another commenter asked RSPA to consider
adopting a recommended practice for applying protective coatings on
tank cars that is now under development by the National Association of
Corrosion Engineers.
With regard to these comments, this final rule simply modifies
Secs. 179.100-4 and 179.200-4 by removing the exception for
polyurethane-foam insulations. Each of the current sections, and the
proposed rule, only require a protective coating on a carbon steel tank
shell and tank jacket. Concerning the comment on acid-resistant
coatings, RSPA agrees that applied coatings should prevent any
corrosive attack to the tank metal. RSPA and FRA will explore, in
cooperation with the AAR, CMA, and RPI, the need for and development of
acid-resistant coating standards.
NTSB commented that the proposed rule does not sufficiently address
the potential problem of existing tank cars. NTSB further noted that a
requirement to apply a protective coating on an existing tank car, only
when the jacket is removed to repair a tank, cannot ensure that
corrosion problems will be detected before the tank corrodes through
and releases its lading. NTSB stated that, at a minimum, tank cars
currently in use without protective coatings should be inspected
periodically for corrosion damage and tank cars found with corrosion
damage should be required to have appropriate repairs.
We agree with NTSB, and in this final rule require, under Docket
HM-201, new inspection intervals for materials that are corrosive to
the tank and a thickness performance measurement to ensure that the
tank shell is not corroded below the minimum shell thickness as
prescribed by the AAR. RSPA and FRA believe that HM-201 is responsive
to NTSB's concerns.
In this final rule, RSPA is requiring protective coatings for all
new tank cars and for existing tank cars when a repair to the tank car
requires the complete removal of the jacket, as suggested by
commenters.
K. Halogenated Organic Compounds (HOC)
To address a 1991 NTSB safety recommendation,14 RSPA proposed
in the NPRM to require the use of a tank car with enhanced puncture
resistance if the tank is used to transport one or more of the 100 HOC
compounds listed in 40 CFR Part 268 Appendix III. The Appendix III list
was developed by EPA pursuant to statute (42 U.S.C. 6924) in order to
prohibit the land disposal of certain compounds having a carbon-halogen
bond, and that have the potential to harm human health and the
environment (these EPA compounds were identified as the ``California
List'' under the statute [See also 40 CFR 268.32]).
\14\Transportation of Hazardous Materials by Rail, National
Transportation Safety Board Safety Study, Report NTSB/SS-91/01,
National Transportation Safety Board, Washington, D.C. (Safety
Recommendations R-91-11 and R-91-12).
---------------------------------------------------------------------------
Many commenters opposing regulation of the EPA compounds suggested
that RSPA should continue to only regulate the compounds identified as
hazardous substances in Appendix A to Part 172. Commenters further
suggested that DOT should not consider the HOC concentration threshold
for those compounds. Several commenters stated that the regulatory
action proposed by RSPA is unnecessary, that RSPA should discontinue
its efforts to regulate these EPA compounds, and that RSPA should not
consider extending enhanced tank car standards to those carrying the
more than 1,000 chemicals prohibited from land disposal.
API, CMA, and several other commenters suggested that the threshold
quantities for the EPA compounds are too low for transportation
purposes. The EPA threshold in 40 CFR 268.32 is 1,000 milligrams per
liter (mg/l) for liquids and 1,000 milligrams per kilogram (mg/kg) for
solids.
CMA furnished a benefit/cost analysis, prepared by Reebie
Associates, that used 1992 TRAIN II data; thereby updating the previous
work performed by AAR, CMA, and RPI addressed in the NPRM. The CMA
report shows that a total of 3,893 tank cars transported an EPA
compound. CMA's list and the number of tank cars used for such
compounds follows:
------------------------------------------------------------------------
AAR/CMA/RPI
Hazardous CMA's 1992 agreement Currently in
substances population (based on pressure Remaining
1988 data) tank cars
------------------------------------------------------------------------
1,1-
Dichloroethylen
e.............. 1 ............ ............ 1
1,2-
Dichloroethane. 236 236 ............ ............
1,2-
Dichloropropane 31 ............ ............ 31
Carbon
tetrachloride.. 312 312 ............ ............
Chlordane....... 10 ............ ............ 10
Chlorobenzene... 105 105 ............ ............
Chloroethane
(ethyl
chloride)...... 106 ............ 106 ............
Chloroform...... 227 227 ............ ............
Chloropropene... 7 ............ ............ 7
CIS 1,3-
dichloropropane 42 ............ ............ 42
Dichlorodifluoro
methane........ 224 ............ 224 ............
Dichlorofinrorom
ethane......... 2 ............ ............ 2
Dichlorofluorome
thane.......... 1 ............ ............ 1
Hexachlorocyclop
entadiene...... 8 ............ 8 ............
[[Page 49057]]
Methylene
chloride....... 2 2 ............ ............
o-
Dichlorobenzene 15 15 ............ ............
p-
Dichlorobenzene 82 82 ............ ............
Pentachloropheno
l.............. 10 ............ ............ 10
Tetrachloroethan
e.............. 13 13 ............ ............
Trichlorobenzene 6 ............ ............ 6
Trichloromonoflu
oromethane..... 4 ............ 4 ............
Vinyl chloride.. 2,449 ............ 2,449 ............
-------------------------------------------------------
Totals...... 3,893 992 2,791 110
------------------------------------------------------------------------
Commenters stated that RSPA should not include materials that are
transported as a solid because, when released, the clean up of these
materials is easily achieved. This statement assumes that accidents
will not occur near lakes, rivers or streams, or that rainfall will not
carry solid residue to such water sources. It is RSPA's and FRA's
experience that these types of accidents can occur as evidenced by the
metam sodium spill in the Sacramento River in California.
As discussed in the NPRM, these materials were also evaluated by
the AAR in an effort to identify materials that have the potential to
harm human health and the environment. The AAR analyzed the EPA
compounds using a computer model based on EPA and standard chemical
dispersion equations. The AAR model describes a method of evaluating
the relative environmental hazard of chemicals shipped in tank
cars.15 In addition to the computer model, the AAR surveyed the
railroad industry for the clean-up costs associated with a spill of an
EPA compound. The AAR considered in their analysis: (1) Compounds that
were permitted in non-pressure tank cars by the DOT in 1988; (2) at
least one shipment of the compound reported to TRAIN II16 in 1988;
(3) the compounds with an EPA reportable quantity (RQ) of less than
1,000 pounds in 1988; (4) the compounds prohibited from land disposal
by the EPA; and (5) the compounds suggested by the railroads' hazardous
materials or environmental staff, or the AAR contractor on the project.
The results of the 1988 survey identified 10 compounds, transported in
class DOT 111A tank cars at that time, that pose a potential threat to
human health and the environment. These compounds were:
\15\Lowenbach, William, A., Consequence Models of Hazardous
Materials Releases on Railroads, Association of American Railroads
(1989), Washington, D.C.
\16\The Association of American Railroads (AAR) data network,
Tele-Rail Automated Information Network (TRAIN II), collects
information on approximately 90 percent of the rail traffic
originating and terminating in the United States. Users of the
network can trace individual car movements or gather information on
a particular cargo moving by rail. The AAR uses the data to develop
statistical trends in both car movement and commodity flow.
Carbon tetrachloride
Chlorobenzene
Chloroform
Dichlorobenzene
Ethylene dibromide (1,2-Dibromomethane)
Ethylene dichloride (1,2-Dichloroethane)
Methyl chloroform (1,1,1-Trichloroethane)
Methylene chloride (Dichloromethane)
Perchloroethylene (Tetrachloroethene)
Trichloroethylene (Trichloroethene)
The results of AAR's analysis show that, within the last 10 years,
the release of these compounds in railroad accidents has resulted in
environmental clean-up costs exceeding $50 million. Even though these
materials accounted for less than one percent of the total volume of
hazardous materials, their releases accounted for 60 percent of all
railroad environmental clean-up costs. Based on the results of the
analysis, the AAR, CMA, and RPI have agreed that by January 1, 2000,
these 10 compounds should be transported only in a DOT 105S200W or a
DOT 112S200W tank car manufactured from AAR TC-128 normalized steel.
One of the 10 compounds, ``ethylene dibromide,'' is a compound that is
poisonous by inhalation (Zone B).
As shown by CMA, 3,893 tank cars were used to transport these ``EPA
compounds''; of that total, ``chloroethane,''
``dichlorodifluoromethane,'' ``hexachlorocyclopentadiene,''
``trichloromonofluoromethane,'' and ``vinyl chloride'' represent 2,791
tank cars, or 72 percent of the total. Because the packaging
authorizations for these compounds currently require the use of classes
DOT 105J, 112J, 112T, 114J, 114T tank cars, these tank cars currently
meet the proposed standard.
As noted above, AAR, CMA, and RPI agreed to use only DOT 105S200W
and 112S200W (or better) tank cars: These compounds are transported in
992 dedicated tank cars. CMA identified an additional 110 tank cars
that are used to transport an EPA compound, but lie outside of the
industry agreement. Because these 110 additional tank cars represent a
potential risk to human health and the environment, RSPA believes it is
reasonable to require the same level of protection for the additional
tank cars identified by CMA, based on the 1992 TRAIN II data, as those
identified by the AAR, CMA, and RPI, based on the 1988 TRAIN II data.
It simply cannot be argued that the shipment of an EPA compound
identified after 1988 poses less risk in transportation than if the EPA
compound would have been identified by the AAR, CMA, and RPI in 1988.
Furthermore, because the AAR, CMA, and RPI agreement does not preclude
the use of a non-protected tank car in transportation by any one member
or nonmember of the agreement, such cars may still be used.
After considering each of the comments, RSPA agrees it should only
regulate those EPA compounds listed in the HMR. After reviewing the 100
EPA compounds (listed in 40 CFR 268 Appendix III), RSPA found that all
but 16 of the compounds are currently identified as a hazardous
substance. The 16 compounds are:
Bis(2-chloroethoxy)ethane
Bis(2-chloroethyl)ether
Bromomethane
2-Chloro-1,3-butadiene
3-Chloropropene
1,2-Dibromomethane
Dibromomethane
Hexachlorodibenzo-p-dioxins
Hexachlorodibenzofuran
Iodomethane
Methylene chloride
Pentachlorodibenzo-p-dioxins
[[Page 49058]]
Pentachlorodibenzofuran
Tetrachlorodibenzofuran
Tribromomethane
1,2,3-Trichloropropane
More than 30 of the compounds are listed by proper shipping name in the
Sec. 172.101 Table. As a group, the EPA compounds include: volatiles
(35 compounds); semivolatiles (33 compounds); organochlorine pesticides
(20 compounds); phenoxyacetic acid herbicides (3 compounds); PCBs (all
PCBs); and dioxins and furans (7 compounds).
Based on this review, this final rule requires that, when the EPA
compounds listed in the HMR are transported in large capacity tank
cars, the tank cars must conform to a limited and designated
specification with greater protection in accidents. Also, to ensure the
proper identification and packaging of these materials, RSPA is listing
(with the exception of Class 2 materials [compressed gases], PIH
materials, and the 16 materials not now identified as hazardous
substances) in Sec. 173.31(f), all EPA compounds listed in 40 CFR Part
268, Appendix III. As explained elsewhere in the preamble, RSPA is no
longer authorizing Class 2 materials or PIH materials in low-pressure
tank cars, e.g., class DOT 111A.
Because RSPA is listing the EPA halogenated-organic compounds as
hazardous substances, in this final rule, the threshold quantity is the
reportable quantity of the hazardous substance. As an example, if the
material in the tank car (including its mixtures and solutions) (1) is
listed in Appendix A to Sec. 172.101, (2) is in a quantity that equals
or exceeds the reportable quantity (RQ) of the material listed in
Appendix A, and (3) is listed in Sec. 173.31(f), it must be transported
in a tank car of limited and designated specification to offer greater
protection in the event of an accident.
In the NPRM, RSPA proposed that any of the halogenated organic
compounds identified by EPA must be transported in a tank car meeting
DOT 105S200W, DOT 112S200W with an 11-gauge metal jacket, or DOT
112S340W without a metal jacket. RSPA stated that the metal jacket and
head protection on these tank cars blunt the impacting forces from
couplers, wheels, track, and other objects along the carrier's right-
of-way. According to FRA research, this blunting effect is directly
proportional to the thickness of the tank jacket or head shield and is
effective in preventing tank punctures.17 The NPRM would have
allowed the use of any class DOT 105 or DOT 112 tank car regardless of
its date of construction. Older tank cars would be allowed, including
those constructed with an older steel specification, such as ASTM A212
Grade B. Because the older steels have less puncture resistance than
the steels currently in use, the NPRM proposed the use of an external
metal jacket to help blunt any impacting force, as a result of an
accident, to the tank shell.
\17\Coltman, M., & Hazel, M., Jr., Chlorine Tank Car Puncture
Resistance Evaluation, Report DOT/FRA/ORD-92-11, Federal Railroad
Administration (1992), Washington, D.C.
---------------------------------------------------------------------------
At the January 6, 1994, public hearing, a commenter asked RSPA to
consider the use of a non-jacketed DOT 112S200W tank car, provided that
the tank car was constructed from an AAR normalized high-strength steel
specification, AAR TC-128. This steel specification has high tensile
and yield strength. In addition to the higher tensile and yield
strengths, commenters stated that normalization of the steel adds extra
puncture resistance. A commenter further stated that a tank car
constructed from the AAR's TC-128 steel specification would provide a
level of puncture resistance comparable to that of tank cars proposed
for use in the NPRM, and would also render a indisputable benefit/cost
ratio. Upon further review, RSPA agrees that a tank car constructed
from AAR TC-128, normalized, would provide a level of puncture
resistance equivalent to a tank car constructed from any steel
specification proposed in the NPRM. In this final rule, RSPA has
provided for the use of a DOT 112S200W (non-jacketed tank car)
constructed from AAR TC-128 normalized steel as an authorized
packaging, as suggested by the commenter.
L. Implementation of New Requirements
In the NPRM, RSPA proposed two implementation dates. Under ``Option
A,'' most of the compliance dates were set at 10 years from the
effective date of this final rule. This is a period that also coincides
with the duration frequently specified in typical full-term tank car
leases, whether a true lease or a financing vehicle; and with the
``thorough inspection'' interval for tank cars in Interchange Rule
88.B.2.18 Under ``Option B,'' RSPA proposed that certain tank car
types and car/commodity combinations be considered for shorter retrofit
periods, with 5 years given to bring existing cars into compliance. For
instance, aluminum and nickel tank cars are more vulnerable to
puncture, and tanks used for transporting PIH materials present special
hazards.
\18\Field Manual of the Interchange Rules, adopted by the
Association of American Railroads, Mechanical Division, Washington,
D.C., 1992. At intervals not to exceed 10 years, major components of
the car must be inspected, including body bolsters and center
plates, center sills, crossbearers, crossties, draft systems and
components, end sills, side sills, and trucks.
---------------------------------------------------------------------------
Option A was supported by commenters. Although urging RSPA to adopt
the 10-year time limit, RPI stated that, because of start-up
complexities, it will not be reasonable to accomplish this on a 10-
percent per year basis. Instead, RPI suggested that its members were
willing to modify 50 percent of the fleet in the first 5 years and 50
percent in the second 5 years. This accomplishes the desired goal while
minimizing scheduling problems and maximizing efficiency.
Option B was supported by NTSB who stated that RSPA should require
tank-head protection, within 5 years, for all class DOT 105 tank cars
having capacities of less than 70 kl (18,500 gallons) when used to
transport a Division 2.1 material (flammable gas).
Most commenters supported the 10-year modification program for
existing tank cars. RSPA believes, however, that a 5-year modification
program is more appropriate for class DOT 105 tank cars that have a
capacity less than 70 kl (18,500 gallons) when used to transport a
Division 2.1 material. Mandating an accelerated modification program
for these particular tank cars will ensure that those cars presenting
the greatest risk are modified first. Therefore, this final rule
requires that each tank car built on or after the effective date of
this final rule conform to this final rule. For tank cars built prior
to the effective date, the phase-in period is 10 years: at least 50
percent of the fleet in the first 5 years and the balance in the second
5 years. The phase-in-period for tank cars transporting a Division 2.1
material is 5 years, with at least 50 percent within 2\1/2\ years and
the balance in the second 2\1/2\ years. For existing tank cars
constructed with an internal self-energized manway located below the
liquid level of the lading, the compliance date is the effective date
of this final rule.
III. Docket HM-201--Detection and Repair of Cracks, Pits, Corrosion,
Lining Flaws and Other Defects of Tank Car Tanks
A. Background
On September 16, 1993, RSPA published in the Federal Register a
NPRM under Docket HM-201; Notice No. 93-15 [58 FR 48485]. The NPRM
contained proposals to: (1) require the development and implementation
of a quality assurance program (QAP) at each facility that builds,
repairs, or ensures the structural integrity of tank
[[Page 49059]]
cars; (2) require the use of non-destructive testing (NDT) techniques
in lieu of the current periodic hydrostatic pressure tests for fusion
welded tank cars to more adequately detect cracks in principal
structure elements (PSE), the failure of which could cause catastrophic
failure of the tank; (3) require thickness measurements of tank cars;
(4) allow for the continued use of tank cars with limited reduced shell
thicknesses; (5) increase the inspection and test intervals for tank
cars; and (6) clarify the tank car pretrip inspection requirements.
Readers are referred to the NPRM preamble for a complete background,
including a more extensive discussion of issues and citations to
research data summarized in the final rule.
RSPA received 31 comments in response to the NPRM from members of
the various industries that own, lease, transport, or use tank cars.
RSPA and FRA have given full consideration to all comments in the
development of this final rule. Following is a summary of the written
comments, a summary of the final rule, and the actions taken by RSPA
and FRA in this final rule:
B. Damage-Tolerance Fatigue Evaluations
In 1992, the NTSB issued a report on the inspection and testing of
tank cars. The report disclosed that many tank car defects are not
routinely detected. These defects may suddenly grow to a critical size
resulting in failure of the tank car. The NTSB recommended that FRA and
RSPA develop requirements for the periodic inspection and tests of tank
cars to help ensure the detection of cracks before the cracks propagate
to a critical length. Such requirements would establish inspection and
test intervals based on the defect size detectable by the inspection
and test method used and on the stress level and crack propagation
characteristics of the PSE based on a ``damage-tolerance'' approach.
The Federal Aviation Administration (FAA) defines a structure as damage
tolerant if the structure has been evaluated to ensure that, should
serious fatigue, corrosion, or accidental damage occur within the
operational life of the structure, the remaining structure can
withstand reasonable loads without failure or excessive structural
deformation until the damage is detected (FAA Advisory Circular AC No.
25.571-1A). Damage-tolerance assumes that flaws exist in the structure
and that the design of the structure is such that these flaws will not
grow to a critical size and cause catastrophic failure to the structure
within a specified damage detection period. The damage detection period
depends on the characteristics of each PSE, each element's
susceptibility to severe corrosive environments, the inspectability of
each element, the inspection method, and procedures used and
maintenance practices.
In the NPRM, RSPA proposed to allow tank car owners to use an
alternative inspection and test procedure or interval based on the
completion of a damage-tolerance fatigue evaluation. The evaluation
procedures would be reviewed by the AAR and approved by the Associate
Administrator for Safety, FRA. As stated in the NPRM, FRA believes that
some tank car owners may be able to reduce inspection and test costs by
using damage-tolerance fatigue evaluation procedures that incorporate:
(1) In-service inspection and test using techniques such as ultrasonic
or acoustic emission; (2) sampling of individual designs with a 100
percent inspection and test of the design if a crack is found; (3)
inspection and test intervals unique to each tank car component; and,
(4) inspection and test intervals based on the degree of risk a
material poses (i.e., high risk materials have shorter inspection and
test intervals than those with low risks).
Most commenters stated that the damage-tolerance approach is a
significant step toward advancing the detectability of defects and well
suited to a tank car and its associated structure. They suggested that
RSPA and FRA expand the damage-tolerance approach, for fatigue, to
include other types of damage mechanisms, such as corrosion, corrosion
fatigue, original fabrication defects, stress corrosion cracking,
impact damage, and damage caused by an accident.
RSPA and FRA agree that the use of a damage-tolerance approach to
periodic inspection and test of tank cars would substantially increase
the likelihood of the detection of cracks and crack-like defects before
such defects propagate to a critical size. RSPA and FRA also believe
that the inspection interval for each PSE should be based on the
inspection method used, the stress level in each PSE, and the crack
propagation characteristics of each PSE.
The agencies realize, however, that in order to fully implement a
damage-tolerance program, it will take years for each owner or
manufacturer of a tank car to analyze each element on the tank car, and
to support the results of such analysis with test evidence and service
experience. FRA is currently working with the AAR Tank Car Committee,
the RPI, tank car owners, lessors, and manufacturers to develop
acceptable non-destructive testing techniques, and to develop an
inspection and test program based on damage-tolerance principles. These
programs include finite element analysis of the stub sill and its
attachment to the tank shell to identify the PSE on the tank car that
should be examined, over-the-road tests to define the typical
environmental loading spectrum expected in service, and a damage-
tolerance evaluation of the structure.
In this final rule, RSPA is revising the regulatory text for the
damage-tolerance fatigue evaluation proposed in Sec. 180.509(k). This
revised requirement provides that an acceptable damage-tolerance and
fatigue evaluation include other types of damage mechanisms and is
supported by test evidence and, if available, by service experience.
C. Inspection and Test Intervals
FRA found that cracks may reach a critical size in a PSE within
about 400,000 miles of railroad service [see ``Owners of Railroad Tank
Cars; Emergency Order Requiring Inspection and Repair of Stub Sill Tank
Cars,'' (Emergency Order Number 17) 57 FR 41799, September 11, 1992].
To ensure against premature failure, common procedures for NDT allow
for two opportunities to inspect an item before predicted failure.
Because tank cars travel an average of about 18,000 miles per year and
most cracks become critical at about 400,000 miles of railroad service,
in the NPRM, RSPA proposed an inspection and test interval, based on a
simplified damage-tolerance evaluation, of 10 years to allow for two
opportunities to inspect an item before predicted failure.
For the sake of efficiency, and to increase safety margins for most
cars, RSPA proposed to implement the 10-year inspection and test
interval starting at what would otherwise be the next scheduled tank
hydrostatic pressure test. For tank cars within a 20-year test cycle,
RSPA proposed that the next inspection and test date be the publication
date of this rule plus one half of the remaining years to what would
otherwise be the next scheduled tank hydrostatic test. After that the
tank would require an inspection and test on a 10-year interval.
For materials corrosive to the tank and shipped in non-lined or
non-coated tank cars, RSPA proposed an inspection and test interval
based on the lower of (1) the corrosion rate of the material on the
tank shell or (2) the fatigue life of the tank structure as discussed
above. RSPA and FRA developed a test interval to ensure that the
calculated thickness of the tank at the next inspection and
[[Page 49060]]
test will not fall below the proposed allowable minimum wall thickness.
The inspection and test interval in this case is calculated by
subtracting the actual thickness (measured at the time of construction
or any subsequent inspection and test) from the allowable minimum
thickness and then dividing that difference by the corrosion rate of
the hazardous material on the tank. Consequently, as the shell
thickness corrodes throughout the service-life of the tank, the tank
must receive an inspection and test more frequently.
Commenters supported the proposed inspection and test program for
most tank cars. They suggested, however, that RSPA consider the
availability of tank car facility space and the practicality of
implementing the new inspection and test and quality assurance programs
without immobilizing a large number of tank cars. In particular,
commenters suggested that RSPA not reduce the inspection and test
intervals for tank cars constructed during the 1975-1979 period that
are now subject to a 20-year hydrostatic pressure test interval. As
proposed, these particular tank cars become due for inspection and test
during the years 1995 through 1997. A major oil company stated that
these particular tank cars represent at least 20 percent of its tank
car fleet.
Several commenters stated tank cars used to transport chlorine,
unlike other tank cars, are currently tested every two years. As such,
all 8,000 tank cars in chlorine service would have to be brought in
conformance with the new inspection and test requirements within two
years. One company stated that it maintains 3,000 tank cars in chlorine
service and it would have to inspect 5.7 tank cars per day, which may
not be feasible because companies must first determine efficient
inspection techniques and provide training to inspection personnel.
Commenters further argue that because tank cars that transport chlorine
have an insulation system and a metal jacket, the inspectability of
certain PSE on these tank cars is difficult; accordingly, RSPA should
not mandate the new requirements in the short-term until the industry
and the government specify the acceptable NDT techniques for inspecting
tank cars that have metal jackets.
The RPI suggested that RSPA phase in the new procedures slowly by
beginning with tank cars without a metal jacket and then tank cars
having a metal jacket when appropriate inspection techniques are
developed. Although RPI did not explain the basis for its comment, RSPA
and FRA assume that the reason behind RPI's comment is the difficulty
of inspecting PSE on a tank car having an insulation system covered by
a metal jacket or a thermal protection system; consequently, tank car
facilities will need time to develop the inspection methods and to
train inspection personnel on the use of those methods. Only after
identifying the appropriate inspection method and by training
inspection personnel, will there be a high probability of defect
detection.
Several commenters requested that RSPA not require, in proposed
Sec. 180.509(b)(3), an inspection and test [requalification] of the
tank each time it is transferred into or out of a service that is
corrosive to the tank, which one commenter stated could occur 4 times
per month. Another commenter stated that the program is redundant with
proposed Sec. 180.509(c)(3)(ii) and, therefore, the section should be
deleted. The Chemical Manufacturers Association (CMA) suggested that
RSPA amend the proposal to allow for routine transfers, so long as the
tank car is within the established intervals for the periodic
inspection requirements. A commenter suggested that localized
modifications to a tank, such as modifying nozzles or bottom outlets,
should not subject the tank to a complete requalification.
Based on the comments received, RSPA is not adopting proposed
paragraphs (b) (3) and (4). Paragraphs (b) (5) and (6) are renumbered
accordingly.
RSPA and FRA also agree that local repairs or modifications should
not subject the tank to the full inspection and test program, because
the repair or modification must be done according to Appendix R of
AAR's Specifications for Tank Cars. Appendix R specifies the procedures
for repairs, alterations, and conversions of tank cars and the
appropriate non-destructive testing method to ensure that the repairs,
alterations, or conversions were performed correctly.
RSPA and FRA agree that the new inspection and test methods,
combined with other FRA mandated inspection programs, may cause a
tremendous backlog of tank cars awaiting inspection. Therefore, to
maintain an acceptable level of safety, but also to allow for an
orderly and acceptable phased-in NDT inspection and test program, RSPA
will delay the compliance date of this final rule for 24 months for
tank cars without metal jackets and 48 months for tank cars having a
metal jacket or a thermal protection system. Before the compliance
date, tank cars may be given an inspection and hydrostatic test in
accordance with the current requirements or the requirements contained
in this final rule. After the compliance date, each tank car must be
given an inspection and test according to the requirements contained in
this final rule on or before the next scheduled tank hydrostatic
pressure test date.
D. High-Mileage Tank Cars
FRA realizes that some tank cars can travel in excess of 18,000
miles each year and, by doing so, the tank cars may reach 200,000 miles
of railroad service before their first periodic inspection and 400,000
miles before their second.
The NTSB expressed its concerns that the proposed regulations
recommend, but do not require, more frequent inspections and tests for
tank cars with mileage rates that exceed the average. Further, because
there is no requirement to maintain cumulative mileage on individual
tank cars, the NTSB expressed concern that high-mileage tank cars would
not be identified for the more frequent inspections and tests, thereby
increasing the possibility of a non-detected fatigue crack propagating
and causing a structural failure within the 10-year inspection and test
cycle.
RSPA and FRA agree with the NTSB that high-mileage tank cars should
receive an inspection and test prior to reaching 200,000 miles of
railroad service. However, no requirement for the maintenance or
retention of car mileage records was proposed. Because car owners keep
records of car mileage, the owners can ensure that tank cars having
high-mileage are inspected more frequently than the inspection and test
intervals adopted in this final rule. Current Sec. 173.24(b) provides
that each package used for the shipment of hazardous materials shall be
so designed, constructed, and maintained . . . so that under conditions
normally incident to transportation--the effectiveness of the package
will not be substantially reduced. Thus, an owner has an obligation to
ensure the continuing effectiveness of a tank car. This duty is not
unlike that of an owner of an automobile who replaces the tires on his
or her car when worn and not based on the warranty period. FRA will,
during its inspection activities, assess the need for a rulemaking (1)
to require owners to retain car mileage records and (2) to inspect
their tank cars before the cars accumulate more than 200,000 miles of
railroad service.
E. NDT Techniques
In the NPRM, RSPA proposed to require that the bottom shell of
fusion welded tank cars be inspected periodically by appropriate NDT
techniques, such as optically aided visual inspections, ultrasonic,
[[Page 49061]]
radiographic, magnetic particle, and dye penetrant testing methods, in
lieu of hydrostatic pressure tests.
All commenters supported the use of NDT techniques to assess the
integrity of a tank car in lieu of a hydrostatic pressure test. Several
commenters stated that the use of qualification procedures will require
formal NDT techniques in defined areas where no previous requirements
existed and will improve the overall safety of tank cars.
Several commenters suggested that RSPA should authorize the use of
acoustic emission testing to qualify tank cars for further use. One
commenter stated that acoustic emission testing is widely used in the
chemical process industry to assure the integrity of pressure vessels,
tanks, and piping. The commenter further stated that the overall
reliability of a series of local tests (ultrasonic, dye penetrant,
radiography, etc.) is incorrectly compared with the reliability of a
single global test (hydrostatic, acoustic emission) and that
substitution of multiple local tests for a single global test may
endanger, rather than enhance the safe transportation of hazardous
materials.
RSPA and FRA do not agree with the commenters's conclusion about
the potential danger of multiple local tests as compared with a single
global test. RSPA and FRA believe that multiple local tests, focusing
on known areas of tank car stress, have a safety advantage over single
global tests, at least with the current state of development of
acoustic emission testing in the tank car industry. The NDT methods
mandated by this rule are a safety improvement. As noted immediately
below, the agencies have underscored their belief in the potential
benefits acoustic emission testing offers by granting an exemption that
will permit its development and refinement in a railroad industry
context.
Outside the scope of this rulemaking, but related to it by means of
subject matter, Monsanto Chemical Company applied for a DOT exemption
to use acoustic emission technology, in lieu of the current hydrostatic
retest, for the tank cars it owns. The procedures developed by Monsanto
to support its exemption were recently evaluated under a research
contract administered by the government of Canada. (McBride, S. L.,
Acoustic Emission Tank Car Test Method Review & Evaluation, Transport
Canada Report No. TP 12140E (1994) Montreal, Quebec). The results of
that research show that Monsanto's acoustic emission testing procedures
appear to be sound. The report suggests, however, minor refinements in
the acoustic emission procedures. Taking this into account, RSPA issued
Monsanto an exemption on September 9, 1994 (DOT-E 10589). The following
companies were granted ``party to'' status on the Monsanto exemption:
Union Tank Car Company, Testing Associates, and Physical Acoustics
Corporation.
This final rule does not include acoustic emission testing as an
authorized NDT technique. RSPA and FRA are committed, however, to
explore new technologies for inspecting and testing tank cars and will
continue to evaluate the possibly of authorizing the acoustic emission
testing procedure in the future. In support of this commitment, FRA
issued a research contract to further explore and refine the use of
acoustic emission testing procedure and other NDT techniques in
determining the integrity of insulation and lining covered welds of
tank cars.
F. Leakage Test
In the NPRM, RSPA proposed a leakage test that would include all
product piping with all valves and accessories in place and operative,
except that during the test the tank car facility would remove or
render inoperative any venting devices set to discharge at less than
the test pressure. As proposed, the test pressure would be maintained
for at least 5 minutes at a pressure of not less than 50 percent of the
tank test pressure.
Most commenters opposed the proposed change to use 50 percent of
the tank test pressure as the standard, because these pressures, some
as high as 300 psig, would constitute an unsafe maintenance practice.
RSPA proposed the leak test to ensure that when valves, fittings, and
manway cover plates are replaced on a tank car after an inspection and
test, that valves and fittings are securely applied and in a ``leak-
free'' condition under normal operating pressures. This will help
ensure against product leakage from a valve, fitting, or manway cover
plate should the vapor pressure of the commodity rise after the shipper
loads the tank car, normally on its first trip after an inspection and
test at a tank car facility.
Berwind Railway Service Company suggested conducting the leak test
at 30 psig for tank cars having a test pressure less than or equal to
200 psig and 50 psig for tank cars having a tank test pressure greater
than 200 psig. AAR and RPI supported similar pressures. In the
commenters experience, pressures of this magnitude are effective in
ensuring that tank cars are released from tank car facilities in a leak
free condition.
The suggested leak test pressures are similar to the leak test
pressures currently used to qualify highway cargo tanks. For example,
the leak test for a cargo tank may not be less than 80 percent of the
tank design pressure (or its maximum allowable working pressure
[MAWP]); or, the maximum normal operating pressure when the cargo tank
has a MAWP equal to or greater than 6.9 Bar (100 psig); or, 4.1 Bar (60
psig) when the cargo tank is used to transport liquefied petroleum gas.
After considering the comments, RSPA and FRA agree that a lower leak
test pressure would provide an adequate leak test with less risk to
persons performing the test. In this final rule, RSPA is requiring a
leak test at 30 psig for tank cars having a test pressure less than or
equal to 200 psig and a leak test at 50 psig for tank cars having a
tank test pressure greater than 200 psig.
G. Bottom Shell
FRA has found that principal structural elements (PSE) located
within four feet of the bottom longitudinal centerline are susceptible
to fatigue cracking due to repeated loading conditions. Stress
concentrations in these areas may cause the formation of small cracks
that may not be detected under the current inspection and test
procedures. Because some defects may lie outside the area currently
defined as the bottom shell, such as those in the attachment welds of
bottom discontinuities, RSPA proposed, based on FRA's findings, to
revise the current definition of the bottom shell by enlarging the area
from 60.96 cm (two feet) to 121.92 cm (four feet) on each side of the
bottom longitudinal center line of the tank.
The Chlorine Institute, CMA, and others agreed that experience has
shown that the bottom shell is prone to fatigue cracking. However, all
known fatigue-related defects have originated within two feet of the
bottom longitudinal centerline of the tank, which is the area most
highly stressed in train operation.
RPI's comments referenced a report, ``Final Phase 14 Report on the
Stub Sill Buckling Study,'' that shows, when stub sill tank cars are
subjected to static and dynamic (impact) loads, a complex biaxial
stress field results in the shell area between the stub sills. The
report shows that measured strains are due to a combination of axial
compression and bending components and at high loads, high magnitude
strains occur over certain localized areas. The results of the RPI
report show that the stresses on the bottom longitudinal centerline of
the tank are about 1.8 times the magnitude of the stresses occurring
from two to
[[Page 49062]]
four feet from the bottom longitudinal centerline.
RPI further stated that fatigue damage increases exponentially with
the ratio of stress ranges and that crack initiation and propagation
within the area of two feet from the bottom longitudinal centerline is
much faster than the area two to four feet from the bottom longitudinal
centerline. Based on the Phase 14 report, RPI suggests that the bottom
shell definition should encompass an area that lies below the
horizontal plane of two longitudinal parallel lines extending two feet
on each side from the bottom longitudinal centerline, through the tank
heads. K & K Consultants, Incorporated, who also commented on the Phase
14 report provided a summary of the data and explained that the
principal stresses in the tank are approximately parallel to the bottom
longitudinal centerline, and that the stresses tend to decrease
circumferentially away from the bottom longitudinal centerline.
After consideration of the comments, RSPA and FRA agree that four
feet on each side of the bottom longitudinal centerline is overly
restrictive. Therefore, the current definition of bottom shell in
Sec. 171.8 is retained.
H. Structural Integrity Inspections
In the NPRM, RSPA proposed a structural integrity inspection and
test on all circumferential and longitudinal welds and welded
attachments on the bottom of the tank, within 121.92 cm (4 feet) on
each side of the bottom tank centerline, using one or more non-
destructive test methods. As explained above under the heading ``bottom
shell,'' several commenters stated that this area is more appropriately
defined as within 60.96 cm (2 feet) on each side of the bottom tank
centerline.
FRA has learned that some high-stressed areas lie outside of the
60.96 cm (2 feet) bottom longitudinal centerline area. Brake pipe
supports, body stiffeners, tank anchors, and other attachments and
structures having large welds are examples of high-stressed areas that
may lie outside of this area. As a general matter, the HMR require
reinforcing pads for these high-stressed areas between external
brackets and tank shells if an attachment weld exceeds 6 linear inches
of 0.64 cm (0.25 inch) fillet weld per bracket or bracket leg
(Secs. 179.100-16 and 179.200-19). In its Tank Car Manual, AAR requires
the use of a reinforcing pad if a bracket or attachment welded directly
to the tank could cause damage to the tank, either through fatigue,
over-stressing, denting, or puncturing in the event of an accident. If
a reinforcing pad is used under a bracket or attachment, AAR specifies
that the pad shall not be less than 0.64 cm (0.25 inch) thick. For
further information, see sections E15.01 and E15.02 of AAR Tank Car
Manual.
Further, in an investigation of tank shell cracking, FRA found that
local areas of the tank shell near tank discontinuities are subjected
to the combination of live-load stress in addition to the residual
stress induced by reinforcement pad welds, and that this combination
makes the sensitivity of the welded area near the discontinuity and
reinforcing pad weld susceptible to fatigue crack propagation. After
performing residual stress measurements of retro-fitted tank car
weldments, AAR confirmed FRA's findings that significant tensile
stresses (on the order of 30,000 psi) occur in the vicinity of the
fillet welds having a throat size (weld depth) greater than 0.64 cm
(0.25 inch). In general, fillet welds larger than 0.635 cm (0.25 inch)
are considered structural welds, and AAR requires post weld heat
treatment when these welds, such as interior brackets, supports, and
reinforcement bar pads, have a throat thickness exceeding 0.635 cm
(0.25 inch). For further information see R17.01 of AAR Tank Car Manual.
In its comments to the NPRM, the Sulphur Institute stated that
stress type defects may originate in some attachment fillet welds, such
as those greater than 0.64 cm (0.25 inch) that are currently located
outside of the current bottom shell definition. Examples given were
body stiffener and brake pipe support fillet welds.
RPI gave similar comments by suggesting that the inspection of
attachment welds on the bottom of the tank should be limited to
structure welds, such as transverse fillet welds larger than 0.64 cm
(0.25 inch), the terminations of longitudinal fillet welds larger than
0.64 cm (0.25 inch), and tank shell butt welds within 60.96 cm (24
inches) of the bottom longitudinal center line and between the body
bolsters. When asked to clarify its comments, RPI told FRA that a 0.64
cm (0.25 inch) fillet weld refers to the leg-length (see also the
definitions of ``Size [fillet]'' and ``Full Fillet Weld'' in Section
W2.00 of AAR Tank Car Manual). Furthermore, RPI stated that limiting
the inspection and test requirements to fillet welds greater than 0.64
cm (0.25 inch), would exclude non-structural fillet welds, such as
those used to attach exterior heater coils.
RSPA and FRA agree that the stress concentration effects around
structural attachments will cause the formation of fatigue cracks and,
if these cracks are not detected and repaired during routine
maintenance of the tank car, such cracks will grow to failure. In this
final rule, RSPA requires a structural integrity inspection and test in
those areas known to develop cracks. Such an inspection and test
includes transverse fillet welds greater than 0.64 cm (0.25 inch)
within 121.92 cm (48 inches) of the bottom longitudinal center line,
the termination of longitudinal fillet welds greater than 0.64 cm (0.25
inch) within 121.92 cm (4 feet) of the bottom longitudinal center line,
and all tank shell butt welds within 60.96 cm (2 feet) of the bottom
longitudinal center line. By limiting the required inspection to known
areas of crack initiation, RSPA and FRA can expect an increase in the
probability of defect detection, as well as an improvement in the
reliability of the inspection results and a reduction in inspection
costs.
The Sulphur Institute commented that if the integrity of the
coatings or linings applied to protect tank car tank metal remains
acceptable, there should be no need to remove the coating or lining to
inspect the tank for structural integrity. The purpose of the
structural integrity inspection is to ensure the detection of fatigue
cracks before the cracks progress to a dangerous size, thereby reducing
the residual strength of the tank. In order to inspect each PSE to
confirm structure integrity, tank car facilities may need to remove
portions of the lining or coating. Owners may choose, however, to use a
non-destructive testing method that interfaces between different
materials, with effective penetration, so that there will be no need to
remove the coating or lining. Such non-destructive testing methods
include radiography and ultrasonics.
I. Minimum Shell Thickness
Recognizing that a tank car shell tends to decrease in thickness
over time, RSPA proposed in the NPRM a definite service-life shell
thickness requirement for all areas of the tank shell and heads. The
proposed minimum in-service shell thickness requirement was based, in
part, on an AAR-RPI report, ``Allowable Thickness Reduction from
Minimum Prescribed Thickness of Carbon Steel Tank Car Tanks,'' that
discussed the investigation of shell thickness below the Part 179
construction standard in certain areas. The RPI-AAR report considered
the effects of an overall or localized reduction in the tank wall
thickness from a principal mode of failure--failure of a tank car due
to the effects of fire, fatigue crack growth leading to fracture, and
failure of the tank due to puncture of the heads. The results of the
RPI-AAR report show that
[[Page 49063]]
the effects of a slightly reduced shell thickness on tank cars used to
transport ``ethylene oxide,'' ``butadienes, inhibited,'' ``vinyl
chloride,'' ``propane,'' and ``propylene'' will not have a significant
effect on safety. The NPRM also proposed to allow localized areas of
thickness reduction to have a total cumulative surface perimeter not
exceeding 182.88 cm (72 inches), consistent with the current provisions
in Sec. 173.31(a)(11)(iv).
In its comments to the NPRM, RPI suggested that the 72-inch
cumulative perimeter should apply to the bottom shell only. RPI further
stated that RSPA should allow the rest of the tank shell, excluding the
tank heads, to have an unlimited number of two foot perimeter
reductions, provided such areas of reduction are separated by at least
16 inches (twice the diameter of a circle having a 24 inch
circumference).
AAR also suggested that the permitted local thickness reductions
for non-pressure tank cars should depend on cause. AAR thickness
reduction tables, endorsed by many commenters under an earlier
rulemaking, differentiated between corrosion and mechanical damage for
non-pressure tank cars (see ``Shippers Use of Tank Cars with Localized
Reductions in Shell Thickness,'' 54 FR 8336, 8337, February 28, 1989).
AAR further commented that there is no need to make a distinction
between the cause of damage for pressure tank cars because of the
stricter limits imposed on such cars. AAR proposed that, for non-
pressure tank cars, RSPA should permit a 0.48 cm (0.188 inch) local
thickness reduction in the top shell and 0.32 cm (0.125 inch) local
thickness reduction in the bottom shell for corrosive damage. For
mechanical damage, RSPA should permit 0.32 cm (0.125 inch) local
thickness reduction in the top shell and a 0.16 cm (0.063 inch) local
thickness reduction in the bottom shell. AAR asserts that the stresses
from a given thickness reduction attributed to mechanical damage can be
greater than the same reduction attributed to corrosion damage, because
mechanical damage causes a more abrupt change in the thickness.
After full consideration of the merits of these comments, RSPA and
FRA agree that there should be no overall limit on the amount of
surface area with localized reduced shell thicknesses, provided such
limitations apply only to the top shell of the tank and such areas are
separated by at least 16 inches. Also, RSPA is modifying the thickness
reduction table, as recommended by AAR, and endorsed by several
commenters, to differentiate between corrosion and mechanical damage.
AAR commented that RSPA proposed, in Sec. 180.509(g), maximum
thickness reductions from the original thickness of the tank and not
the required thickness of the tank: a thickness specified in a chart
summarizing specification requirements (e.g., Sec. 179.101-1(a)), or
the result of a calculation (e.g., Sec. 179.100-6(a)). RSPA disagrees.
The proposed section in the NPRM states that--
[a] tank car found with a thickness below the required minimum
thickness after forming for its specification, as stated in Part 179
of this subchapter, may . . . [emphasis added]
AAR further stated that RSPA should include an explicit provision
enabling the owner of a tank car to ``downgrade'' [downrate] the car to
the point where the loss of thickness exceeds the maximum allowed by
the regulation. As RSPA stated in the NPRM under the preamble heading,
``Safety System Inspections,''
[n]othing in the regulations would preclude a tank car owner from
marking a tank as meeting a less stringent specification, such as
re-marking a specification DOT 112J tank car to a DOT 112S or
112J400W tank specification to a DOT 112J340W tank specification
when the tank car no longer conforms to the marked specification.
Downrating is permissible and a tank car owner may mark a tank as
meeting a less stringent specification, such as marking a specification
112A340W tank car to a DOT 111A100W1 tank car when the tank, because of
its shell thickness, no longer conforms to the marked specification.
Owners are reminded that changing the marked specification also changes
the certificate of construction and, when so doing, they must follow
the procedures in Appendix R of AAR's Specifications for Tank Cars (see
Sec. 173.31(a)(4) and (f), and Sec. 179.6).
In its comments, RPI proposed a standardized minimum inspection
pattern for conducting thickness tests. RPI suggests that thickness
readings should be taken at the bottom, one side (90 deg.), and the top
within 6-inches of each circumferential weld for each plate. RPI
further states that corresponding readings should also be taken along
the head circumferential weld seam and another reading at the center of
the tank head. This would result in 32 thickness readings for a four-
ring tank. In addition to the tank shell, two readings would be taken
on the manway nozzle, the top unloading nozzle, and the sump. According
to RPI, if an inspector finds corrosion or other damage that reduces
the shell thickness, additional readings must be taken to more
specifically identify the damaged area.
RSPA is not incorporating a written procedure for conducting
thickness measurements throughout the tank shell to increase the
probability of defect or corrosion detection. RSPA and FRA believe that
such procedures belong in the tank car owner's written maintenance
plans or AAR Specifications for Tank Cars. Throughout this rulemaking,
RSPA and FRA have developed a course of action that outlines where and
what to inspect, but not how to inspect. This approach allows each tank
car owner the flexibility to develop inspection and test procedures
appropriate for each unique tank car, or a series of unique tank cars
based on operating and maintenance experience.
J. Lining and Coating Inspections and Tests
In the NPRM, RSPA proposed an inspection and test requirement for
tank cars with linings and coatings. This would ensure that the lining
or coating is in proper condition for the transportation of hazardous
materials. As proposed, owners of lined or coated tank cars must
determine the periodic inspection interval and inspection technique for
the lining and coating, based on the owner's knowledge of the material
used. The owner would also maintain all supporting documentation used
to make such a determination, such as the lining or coating
manufacturer's recommended inspection interval and inspection
technique, at the owner's principle place of business. Further, the
supporting documentation used to make such inspection interval
determinations and the inspection technique would have to be made
available to FRA upon request.
All commenters supported RSPA's proposed inspection and test
requirement for tank cars with linings and coatings. RPI suggested that
RSPA should specify ``owners of linings and coatings,'' as opposed to
the ``tank car owner,'' to determine the inspection and test technique
and interval--since most shippers own the tank car lining or coating as
opposed to the tank car owner. Mobil Oil Corporation and others
suggested that the regulation should only apply to linings and coatings
installed to protect the tank shell, as opposed to those applied for
lading integrity or quality.
RSPA and FRA agree with RPI and are revising the proposed
requirements to incorporate RPI's suggestions. In this final rule,
owners of linings and coatings in tank cars must determine the
[[Page 49064]]
periodic inspection interval and inspection technique for the lining
and coating, based on the owner's knowledge of the material used. This
will ensure that the lining or coating is in proper condition for the
transportation of hazardous materials. The owner must also maintain all
supporting documentation used to make such a determination, such as the
lining or coating manufacturer's recommended inspection interval and
inspection technique, at the owner's principle place of business. The
supporting documentation used to make such inspection interval
determinations and the inspection technique must be made available to
FRA upon request.
Further, in Sec. 180.509, RSPA is revising paragraphs (c)(3)(i) and
(iii)(A) to require an inspection and test of the lining or coating
only when the lining or coating is applied to protect the tank shell
from a lading such as hydrochloric acid.
K. Safety System Inspections
In the NPRM, RSPA proposed to add explicit requirements for the
inspection of thermal protection systems, tank head puncture resistance
systems, coupler vertical restraint systems, and devices used to
protect discontinuities. If, after an inspection, one or more of these
systems do not conform to the applicable specification requirements
contained in Part 179, renewal or repair of the system is necessary to
continue the qualification of the tank car. RSPA received two comments
on this proposal, both indicating support.
In this final rule, RSPA is adopting the requirements for the
inspection of these safety systems.
L. Quality Assurance Program (QAP)
In the NPRM, RSPA proposed to require that each tank car facility
establish a Quality Assurance Program (QAP) to detect non-conformities
during the manufacturing, repair, or inspection and test process. A
tank car facility means an entity that manufactures, repairs, inspects,
or tests tank cars to ensure that the tank cars conform to Parts 179
and 180, that alters the certificate of construction of the tank car,
or that verifies that the tank car conforms to the specification.
All commenters endorsed the QAP proposal; however, several
commenters suggested that RSPA delay the effective date for at least 18
months so that tank car repair facilities will have the opportunity to
develop a QAP. In its comments, AAR supported RSPA's QAP requirements
and further stated that the QAP developed by RSPA is consistent with
AAR's quality assurance requirements.
Several commenters asked RSPA to clarify whether or not a tank car
facility includes a shipper's loading facility where items such as
gaskets and manway bolts are normally inspected and replaced as part of
a ``pre-trip'' inspection. It is not the intention of RSPA to include
within the definition of a tank car facility a shipper's facility where
pre-trip inspections are performed. Generally, a tank car facility
evaluates the tank structure to ensure that, if serious fatigue,
corrosion, or accidental damage occurs within the inspection and test
interval, the remaining structure can withstand reasonable loads
without failure or excessive structural deformation. A shipper, on the
other hand, ensures by inspection that the tank is in proper condition
for transportation from point of origin to destination.
Based on the comments received, RSPA is requiring each tank car
repair facility to develop a QAP that has the means to detect any
nonconformity in the manufacturing, maintenance, or repair process and
that has the means to prevent its recurrence. Furthermore, the QAP must
ensure that the finished product conforms to the requirements of the
applicable specification and the regulations in the HMR. RSPA is also
clarifying the definition of a tank car facility to mean an entity that
manufactures, repairs, inspects, or tests tank cars to ensure that the
tank cars conform to Parts 179 and 180, that alters the certificate of
construction of the tank car, that ensures the continuing qualification
of a tank car by performing a function prescribed in Parts 179 or 180,
or that makes any representation indicating compliance with one or more
of the requirements of Parts 179 or 180. This language mirrors that for
the qualification of highway cargo tanks (see Sec. 180.2). A shipper
that inspects a tank car solely to ensure that the tank car is safe for
transportation is not performing a periodic qualification function. On
the other hand, a shipper who continues the qualification of a tank
car, by performing a function described in Parts 179 or 180, meets the
definition of a tank car facility.
M. Inspection Requirements Prior to Transportation
The current regulations, at Sec. 173.31(b)(3), require that the
shipper inspect a tank car before releasing it into transportation to
ensure that, among other things, the closures are in a ``tool-tight,''
secure condition. Further, closures on the tank (under
Sec. 173.24(f)(1)(ii)) must be so designed and closed that ``under
conditions (including the effects of temperature and vibration)
normally incident to transportation . . . the closure is secure and
leakproof.''
RSPA and FRA proposed in Sec. 174.68 that tank cars be inspected
prior to transportation as an amendment to the current requirements
because of their concerns about tank cars in transportation with loose
closures. Since 1989, FRA inspectors have found loose closures on tank
cars containing hazardous materials more than 23,000 times. In that
same period, RSPA has received about 1,100 to 1,200 incident reports
each year on tank cars that had released product, often as a result of
a loose closure. Those releases resulted in injury to 85 railroad
employees. This history shows that more needs to be done to ensure that
tank cars conform to the regulations when offered for transportation.
It is FRA's experience that properly designed and secured closures
(closures meeting the standards of Secs. 173.24 and 173.31) do not
become loose during transportation and that most of the incidents
reported to RSPA reflect poor pre-trip preparation of the tank car
prior to offering it for transportation. In order to clearly state the
offerors responsibility for pre-trip inspection of a tank car,
Sec. 174.68 in the NPRM proposed a rebuttable presumption against a
proper pre-trip inspection if unsecured closures were found in transit.
RSPA and FRA believe that aligning the inspection requirements in
current Sec. 173.31(b) with the design and operations requirements in
Sec. 173.24 will clarify their full intent, foster compliance with
safety standards, and improve hazardous materials transportation
safety. Comments on the proposed Sec. 174.68 came from most of those
filing responses to the NPRM and they covered five aspects of the
proposal. First, several commenters argued that Sec. 174.68 was the
wrong place for pre-trip inspection requirements, that, as shipper
responsibilities, they belonged in Part 173. RSPA and FRA agree and the
final rule includes pre-trip inspection in Sec. 173.31.
Second, several commenters said that the proposal raised the duty
of care for pre-trip car preparation to an all but impossible level.
Current Sec. 173.31(b)(1) requires that ``the shipper must determine to
the extent practicable, that . . . fittings are in proper condition. .
. .'' [emphasis added] The origin of the phrase ``to the extent
practicable'' in Sec. 173.31(b) has its roots in the Interstate
Commerce Commission's (ICC) regulations prior to 1960. In those
[[Page 49065]]
regulations, the ICC required shippers, before loading the tank car, to
examine the tank and each appurtenance to see that the safety and
outlet valves, safety vents, the excess flow valves (if any), the
closures of all openings, and the protective covers of all
appurtenances were in proper condition.
In a letter dated July 10, 1959, to AAR, the Manufacturing
Chemists' Association (MCA) stated that the addition of the words ``to
the extent practicable'' in the tank car loading section was to clarify
the purpose of the regulations and to make the regulation more
realistic and to eliminate from the regulation items which were either
very difficult to inspect or very expensive to inspect such as a full
inspection of safety relief valves or excess flow valves. Read
literally, the regulation at that time would impose a duty on the
shipper to disassemble and inspect safety valves and excess flow valves
prior to each trip.
As a result of the MCA letter in 1959, AAR petitioned the ICC to
amend the current regulations by inserting the phrase ``to the extent
practicable'' in the tank car loading section. The ICC agreed and the
new phrase went into the regulations on March 23, 1960, under Order
Number 42. From the beginning, this phrase was meant to reflect the
practical impossibility of, for instance, taking the valves apart
before each trip; the additional language was not intended to excuse
poor pre-trip preparation. This final rule does not enlarge the ``to
the extent practicable'' standard.
Third, several commenters seemed to confuse the essential elements
of the loose closure violation by arguing that evidence of a leak (or
release of product) in transit does not necessarily prove the lack of a
pre-trip inspection. They mistakenly believed that the proposal focused
on releases of hazardous materials rather than the broader fault: loose
fittings and closures. FRA and RSPA agree that leaks can develop in
transit from sources other that insecure closures, the failure of a
rubber lining and the failure of a frangible disc are two possible
examples. This provision was developed from the requirement in the
current Sec. 173.31(b) that closures must be secured in place with an
appropriate tool, and the final rule makes no changes in that
requirement.
Fourth, many commenters argued that the condition of tank cars in
transit is the responsibility of the railroads, that it is their duty
to ensure that the closures are, and remain, tight. RSPA and FRA note
that current Sec. 173.31(b)(3) requires the shipper to make closures
``tool tight'' prior to shipping and that Sec. 173.24(b) and (f)
require closures to be designed, maintained, and closed so that ``under
conditions (including the effects of temperature and vibration)
normally incident to transportation'' they will remain secure.
Responsibility for tight closures must rest primarily with the offeror.
The railroads' duty to inspect a tank car is aimed at detecting obvious
leaks and defects in the running gear of the vehicle. FRA's pre-
departure inspection requirements--applicable to all trains whether or
not carrying hazardous materials--are found at 49 CFR 215.13. Appendix
D to Part 215 describes the inspection to be performed by a train crew,
``At each location where a freight car is placed in a train and
[designated inspectors] are not on duty. . . .'' Appendix D requires
the train crew to reject a placarded hazardous materials tank car from
which lading is leaking. As the National Industrial Transportation
League said in its comments, ``The key issue in determining the
regulatory responsibilities under the HMR should be to determine which
functions parties actually performed, or should have performed.'' This
final rule is not intended to, nor does it, change these essential
relationships.
Fifth, several commenters argued that the proposed rebuttable
presumption will be impossible to meet. The proposed rule states
examples (derailment and vandalism) that will rebut the presumption,
but they are not intended to be exclusive. In FRA's experience in
discussing alleged violations with shippers over the past few years,
the following circumstances have led to either termination or a penalty
amount significantly reduced from that originally proposed, depending
on the facts and circumstances of each case:
Delivery to a mistaken destination and subsequent
rerouting to the original destination,
Erroneous spotting at a repair facility,
Actual delivery to the consignee prior to inspection,
Abnormally rough handling by a railroad,
Gaskets, otherwise secure at the start of the trip,
deteriorating enroute in a manner the offeror could not have foreseen.
One commenter cited case law on irrebuttable presumptions. RSPA and
FRA agree with the commenter that a presumption impossible to rebut
would not be proper; for the reasons given, RSPA and FRA do not view
the presumption in the regulation published today as impossible to
rebut.
In some cases, FRA has seen pre-trip inspection check lists that
were at obvious odds with the conditions discovered on the car. The
rebuttable presumption stated today is not designed to make enforcement
``easier,'' it is designed to make responsibility more certain. For
most shippers of hazardous materials, today's rule will not mean a
change in the regulator/regulated relationship.
When FRA issues a Notice of Proposed Violation for an alleged
violation of the HMR, the respondent (railroad, shipper, or
manufacturer) is afforded the opportunity to investigate the charges
and to collect factual evidence to mitigate or dismiss the case.
Respondent has the opportunity for a hearing. FRA, or an Administrative
Law Judge, considers respondent's submissions, together with the
factors in 49 U.S.C. Sec. 5123(c), before reaching a decision. The
standard in this final rule does not change the process by which FRA
enforces railroad related hazardous materials violations. FRA expects
that, by clarifying the responsibility of the shipper, there will be
fewer loose closures on tank cars and fewer injured railroad employees.
Several commenters mentioned mishandling, even abusive handling, by
the railroads. FRA's own studies have demonstrated that overspeed
impacts in railroad switching operations are far from a rarity, but FRA
is not aware that overspeed impacts will loosen the threaded fasteners
securing lading retention fittings on a tank car. Overspeed impacts can
cause severe structural damage, lessen the service life of the car, and
cause frangible safety vent discs to rupture. In such cases,
enforcement actions against the railroads are appropriate, and FRA
pursues them. One shipper, PPG Industries, Inc., put impact recorders
on a test fleet of 50 tank cars operated out of its Lake Charles,
Louisiana plant. The impacts in excess of 6G's (about 8 miles per hour)
between July 1992 and December 1993 are documented in PPG's comments in
this docket. Because they are limited in geographic scope, RSPA and FRA
cannot say that this data presents a typical picture, nation-wide, but
PPG's charts are graphic evidence, arranged by railroad and by
terminal, that railroad tank cars are subject to stresses well above
their optimum operating environment.
In the final rule, RSPA is articulating a rebuttable presumption
standard aimed specifically at loose closures on tank cars. The
statement of this presumption in Sec. 173.31(d)(2) does not mean,
however, that there is a different standard for railroad tank cars than
for
[[Page 49066]]
other packagings used to transport hazardous materials. The ``secure
and leakproof'' standard established in Sec. 173.24(f) applies to
closures on all packagings used for transportation. If a hazardous
materials package is discovered with loose closures, either the
closures were not designed properly or they were not tightened
properly. Neither RSPA nor FRA are aware of hazardous materials
packagings designs that allow closures to loosen in transit. Hence the
presumption that, when an inspector discovers a loose closure, it was
not tightened properly. RSPA has made the presumption explicit for
railroad transportation because FRA's enforcement experience, discussed
earlier, proves the need to focus responsibility on those who prepare
hazardous materials for transportation.
The following table lists the adopted paragraphs or sections and,
where applicable, the corresponding paragraph or section contained in
the current HMR. In some cases, the cross-references are to provisions
which are similar to, but not identical with current provisions.
------------------------------------------------------------------------
New section Old section
------------------------------------------------------------------------
173.31(a)(2)............. 173.31(a)(4) [except 4th and 5th sentence].
173.31(a)(3).............
173.31(a)(4)............. 173.31(a)(7) [1st sentence after ``Effective
July 1, 1991...'' and preceding ``..., as in
effect on November 16, 1990''].
173.31(a)(5)
173.31(a)(6)............. 173.31(a)(3) [1st sentence].
173.31(a)(3)(i).
173.31(b)(1)............. 173.31(a)(5) [except last sentence].
173.31(b)(2)............. 173.31(a)(12).
173.31(a)(15) [1st sentence preceding
``...nonreclosing pressure relief
devices.''] [2nd preceding ``...provided
that the liquid...''] [3rd sentence
preceding ``...breather holes are not...''].
173.31(b)(3)
173.31(b)(4)
173.31(b)(5) .............................................
173.31(b)(6)
173.31(c)................ 173.31(a)(14) [1st sentence preceding
``...equal to or greater than...''].
173.31(a)(14)(i) [1st sentence preceding
``...ullage space or dome of tank.''].
173.31(a)(14)(ii).
173.31(a)(14)(iii).
173.31(d)(1)
173.31(e)(1)............. 173.31(a)(17).
173.31(e)(2)
173.31(f)
173.314(c), Note 2....... 173.314(c), Note 25.
173.314(c), Note 3....... 173.314(c), Note 21.
173.314(c), Note 4....... 173.314(c), Note 20.
173.314(c), Note 6....... 173.314(c), Note 12 [except 1st and last
sentence].
173.314(c), Note 7....... 173.314(c), Note 18 [1st sentence preceding
``...g, when offered for transportation.''].
173.314(c), Note 8....... 173.314(c), Note 19 [1st sentence preceding
``...g, when offered for transportation.''].
179.7
179.16................... 179.100-5.
179.18................... 179.100-4.
179.20
179.22................... 179.100-21.
179.105-8.
179.200-25.
179.203-3.
Appendix A to Part 179... 179.105-5 (b) and (c).
Appendix B to Part 179... 179.105-4 (d) and (e).
Subpart F to Part 180
180.501
180.503
180.505
180.507
180.509
180.511
180.513
180.515
180.517
180.519
------------------------------------------------------------------------
IV. Review by Section Summary
Part 171
Section 171.7(a)(3). The 49 CFR reference sections for the
Association of American Railroads standards and for a Compressed Gas
Association standard are added, revised or removed, as appropriate, to
reflect the changes in this rulemaking.
Part 172
Section 172.101. In the HMT, three special provisions are removed.
Special Provision ``B41,'' appearing in column (7) of the entries for
benzyl chloride, fluorosulfonic acid, and titanium tetrachloride is no
longer necessary due to the new inspection and test intervals adopted
in this final rule. Special Provision ``B43,'' appearing in column (7)
of the entries for carbon dioxide, refrigerated liquid, hydrogen
chloride, refrigerated liquid, and vinyl fluoride,
[[Page 49067]]
inhibited, also is no longer necessary because of the new inspection
and test requirements. For the Division 2.1 (flammable gas) entries
ethyl chloride and ethyl methyl ether, Special Provision ``B63'' is
removed, thus prohibiting the use of tank cars without head protection
or thermal protection.
Section 172.102. As discussed above, Special Provisions ``B41'' and
``B43'' are removed. The inspection and test intervals (i.e., 5-3-1)
specified in Special Provision ``B41'' and the nondestructive test
requirements specified in Special Provision ``B43'' are incorporated
into Subpart F of Part 180. Special Provision ``B63'' appears only in
the entries ethyl chloride and ethyl methyl ether and, therefore, in
paragraph (c), is removed. Special Provision ``B64'' is amended by
changing the head-protection section reference ``Sec. 179.105-5'' to
read ``Sec. 179.16,'' and Special Provision ``B79'' is amended by
changing the head- and thermal-protection section references
``Secs. 179.105-4 and 179.105-5'' to read ``Sec. 179.16 and 179.18''.
Part 173
Section 173.31. The section heading is revised to read ``Use of
Tank Cars.'' This section also is completely revised and reorganized
for clarity.
New paragraph (a)(1) corresponds to the language in the HMR for
cargo tanks and portable tanks (see Secs. 173.32c(a) and 173.33(a)).
The section also includes reference to certain ``AAR'' specification
tank cars that are authorized for hazardous materials service in the
HMR (see Secs. 173.241 and 173.242). When these tank cars are used for
the transportation of hazardous materials, the tank cars must meet the
minimum specification for new construction as required by AAR.
New paragraph (a)(2) is essentially current Sec. 173.31(a)(4). The
first, second, and third sentences are revised to clarify the use of
the term ``authorized.'' Prior to December 19, 1957 (ICC Order No. 33),
the regulations stated that:
[T]ank cars and appurtenances may be used for the transportation
of any commodity for which they are authorized, as indicated on the
certificate of construction. When a car is to be used for the
transportation of a commodity other than those approved on the
certificate of construction, it must be approved for such loading by
the A.A.R. Tank Car Committee. Changes in fittings or commodity
stencilling required to transfer a car from one service to another
as authorized on the certificate of construction, may be made only
be the owner or owner's authorized agent * * *.
As evidenced by the language above, the term ``authorized'' means
those commodities designated on the certificate of construction and
approved by the AAR Tank Car Committee. Order No. 33 changed the
regulation by removing the phrase ``as indicated on the certificate of
construction'' because many car owners did not have a certificate for
older Class ARA-II (built prior to 1917), ARA-III (built prior to
1927), and some ICC-103 (built after 1927) tank cars. Because this
final rule requires that the original and subsequent tank car
certificates must be maintained for the life of the car and transferred
with ownership, RSPA is clarifying the purpose of this paragraph by
inserting the phrase ``in this part and specified on its certificate of
construction'' at the end of the first sentence. See Sec. 180.517. The
second and third sentences are modified accordingly. Provisions
contained in the fourth and fifth sentences of current
Sec. 173.31(a)(4), stating that DOT 105A-W, 109A-W, 111A100W4, 112A-W,
and 114A-W tank cars may be used for any commodity for which it is
approved and may be stencilled accordingly, and that a tank car
stencilled to indicate that it is authorized for one commodity may not
be used for any other service, are removed. The stencilling requirement
for these cars is optional and, therefore, not enforceable.
New paragraph (a)(3) provides that no person may fill a tank car
with a hazardous material when the tank car is overdue for periodic
inspection and test. This provision allows the movement of tank cars
containing hazardous material residue to a tank car facility for
inspection and testing.
New paragraph (a)(4) is current Sec. 173.31(a)(7). It removes
reference to a compliance date, now past, and establishes that air
brake equipment support attachments must be welded to pads instead of
directly to the tank shell in conformance with Secs. 179.100-16 and
179.200-19.
New paragraph (a)(5) prohibits the use of an internal self-
energized manway that is located below the liquid level of the lading
on a tank car, beginning on the effective date of this final rule.
After the effective date of this final rule, an exemption would be
required in order to continue to operate such a tank car. This
provision was proposed paragraph (a)(22) in HM-175A.
New paragraph (a)(6) is current Sec. 173.31(a)(3). It removes
specific ``DOT'' class references and explains that any tank car of the
same class with a higher tank test pressure than the tank car
authorized in the HMR may be used. The paragraph is also simplified by
specifying the hierarchy of the letters in the specification marking
that describe special protective systems (e.g., ``J'' for thermally
protected, jacketed cars; ``T'' for thermally protected, non-jacketed
cars; ``S'' for cars with head shields but without thermal protection;
and ``A'' for cars without protective systems).
New paragraph (b)(1), concerning the use of coupler vertical
restraint systems, is current Sec. 173.31(a)(5). It is revised to
require all DOT specification tank cars and any other tank car used to
transport hazardous material to be equipped with a coupler vertical
restraint system. This revision also removes reference to a compliance
date, now past, excepting DOT specification tank cars in nonhazardous
materials service from being equipped with a coupler vertical restraint
system.
New paragraph (b)(2), concerning pressure relief devices, is
current Secs. 173.31(a)(12) and 173.31(a)(15). This revision is
simplified by using the term ``poisonous by inhalation'' (see
Sec. 171.8) in place of the defining criteria.
New paragraph (b)(3) requires head protection for all tank cars
transporting Class 2 materials and tank cars constructed from aluminum
or nickel plate. Tank cars currently equipped with half-head protection
are excluded. The compliance period is 10 years from the effective date
of this rule, except for class DOT 105 tank cars with less than 70 kl
(18,500 gallon) capacity when used to transport a Division 2.1
material, which have a compliance period of 5 years. This provision was
proposed paragraph (a)(19) in HM-175A.
New paragraph (b)(4) requires tank cars transporting Class 2
materials to have thermal protection. Exceptions from the thermal
protection standard are granted for ``chlorine,'' ``carbon dioxide,
refrigerated liquid,'' and ``nitrous oxide, refrigerated liquid,'' and
for tank car tank classes DOT 106, 107A, 110, and 113. This provision
was proposed paragraph (a)(20) in HM-175A. In the NPRM, RSPA did not
propose thermal protection for the commodities identified above (see
proposed Sec. 173.314(k) and (o)). The compliance period is 10 years
from the effective date of this final rule.
New paragraph (b)(5) requires bottom-discontinuity protection for
all existing tank cars transporting a hazardous material. The new
protection requirements conform to paragraphs E9.00 and E10.00 of the
AAR Specifications for Tank Cars, M-1002. Existing tank cars that
conform to Appendix Y of the AAR Specifications for Tank Cars, M-1002,
may continue in use. The compliance period is 10 years from the
effective date of this final rule.
[[Page 49068]]
This provision was proposed paragraph (a)(23) in HM-175A.
New paragraph (b)(6) is added to require tank car owners to
implement measures to ensure the phased-in completion of the
modifications on each tank car subject to this final rule. As discussed
earlier in this preamble, RSPA and FRA have several programs in place
to improve the tank car fleet. Owners, therefore, should develop
careful plans, procedures, and schedules to assure completion of the
modifications before the regulatory compliance date. Paragraph (b)(6)
also requires submission of a yearly progress report to FRA that shows
the reporting mark of each tank car requiring modification, the type of
modification required for each tank car during the previous year, and
the total number of tank cars modified the previous year.
New paragraph (c) was proposed as paragraph (d) in HM-201. This
final rule revises the terms ``un-insulated'' to ``non-insulated,''
``ullage space or dome'' to ``vacant,'' and clarifies that this
provision applies to cars in hazardous materials service only. A new
provision is added in paragraph (c)(3) to require all tank cars
transporting a PIH material to have a tank test pressure of at least
20.7 Bar (300 psi). This provision is consistent with other regulations
adopted under Docket HM-181 for PIH liquids.\19\ Also, several shipping
names appearing in the opening paragraph are revised for consistency
with the proper shipping name as shown in the Sec. 172.101 table.
\19\For further information see Performance-Oriented Packaging,
Docket HM-181, 55 FR 52402 (December 21, 1990). In general, liquid
materials PIH in Hazard Zone A are assigned Special Provision B72
and those in Hazard Zone B are assigned Special Provision B74. These
two special provisions require the use of a 105S, 112J, or a 114J
tank car having a tank test pressure greater than 18 Bar (300 psi).
---------------------------------------------------------------------------
New paragraph (d) reinforces the inspection requirements that must
be fulfilled before a tank car of hazardous materials is offered for
transportation. These provisions were proposed paragraph (a)(4) and
Sec. 174.68 in HM-201. These proposed requirements were revised and
combined based on suggestions made by the commenters.
In new paragraph (e), to clarify that the paragraph applies to
materials that are poisonous by inhalation, the paragraph heading is
revised to read ``Special requirements for materials poisonous by
inhalation.''
New paragraph (e)(1) concerns the use of heater coils. This
provision is essentially current paragraph Sec. 173.31(a)(17). This
provision was proposed paragraph (e) in HM-201.
New paragraph (e)(2) requires that tank cars used for materials
poisonous by inhalation must conform to at least a DOT 105S300W,
105S300ALW, 112J340W, or 114J340W. This provision was proposed
paragraph (a)(21) in HM-175A. It is made consistent with Special
Provision B74 for liquid PIH materials in Zone B. The compliance period
is 10 years from the effective date of this final rule.
New paragraph (f) requires the use of a DOT 105S200W; a DOT
112S200W with an 11-gauge steel jacket conforming to Sec. 179.100-4; a
DOT 112S340W; or a DOT 112S200W tank car constructed from AAR steel
specification TC-128, normalized, for the transportation of certain
listed hazardous substances in Sec. 173.31(f) that pose a potential
threat to human health and the environment. This provision was proposed
paragraph (a)(24) in HM-175A.
Section 173.314. In the table in paragraph (c), the entries are
amended by removing references to the individual tank car
specifications and adding references to the authorized tank car
classes. This change ensures that Sec. 173.314 does not authorize a
tank car having a tank test pressure below the regulatory minimum in
Sec. 173.31(c). The current notes following the table are amended by
redesignating, revising, or removing all tank car ``design
requirements'' as follows (notes that apply to filling limits are
retained):
Note 1, no change.
Note 2 is restated without substantial change and moved to
Sec. 173.314(n).
Note 3 and Note 4 are restated without substantial change and moved
to Sec. 173.314(j), which is applicable to all materials having a
primary or secondary Division 2.1 (flammable gas) hazard.
Note 5 is restated without substantial change for clarity.
Note 6 is restated without substantial change and moved to
Sec. 173.314(o).
Note 7, which restricts the transportation of multi-unit tank cars
tanks (ton containers) to rail and highway only, is removed. RSPA
believes no valid reason exists to restrict the transport of these
units by water. A provision restricting the transport of multi-unit
tank car tanks by air is unnecessary because all multi-unit tank car
tanks exceed the maximum quantity limitations allowed by air.
Note 8 is restated without substantial change and moved to
Sec. 173.314(l).
Note 9 is moved to Sec. 173.314(j) and made applicable to all
materials with a primary or secondary Division 2.1 (flammable gas)
hazard.
Note 10 is restated without substantial change and moved to
Sec. 173.314(m).
Note 11 is restated without substantial change and included in
Sec. 173.314(m).
Note 12 is restated without substantial change. The filling density
requirements are moved to Note 6, and the design requirements are moved
to Sec. 173.314(k).
Note 13 is removed to eliminate duplication of the marking
requirements prescribed in Special Provision B12, Secs. 173.314(a)(5)
and 172.330(a)(1)(i).
Note 14 is removed because it is not referenced in the table.
Note 15 is removed since it is included with the other design
requirements applicable to tank cars used for materials having a
primary or secondary Division 2.1 (flammable gas) hazard in
Sec. 173.314(j).
Note 16, which is currently reserved, is removed.
Note 17, which references Sec. 173.314(g) is removed.
Note 18 is restated without substantial change and moved to Note 7.
Note 19 is restated without substantial change and moved to Note 8.
Note 20 is restated without substantial change and moved to Note 4.
Note 21 is restated without substantial change and moved to Note 3.
Note 22, referencing the requirements in Sec. 173.245, is
incorporated into the table under the entry ``Division 2.3, Zone A
materials.''
Note 23 and Note 24 are removed based on other changes in this
final rule concerning the elimination of grandfather provisions.
Note 25 is restated without substantial change and moved to Note 2.
Note 29 and Note 30 are removed based on other changes in this
final rule concerning the elimination of grandfather provisions.
In addition, the table in Sec. 173.314(c) will reflect the tank car
classes and not the specifications.
Section 173.319. Paragraph (a)(4)(iii) is revised by removing a
parenthetical reference to current Sec. 173.31(c)(13). A requirement
contained in Sec. 173.31(c)(13) prescribing special retest requirements
for class DOT-113 tank cars is revised and moved to new paragraph
Sec. 173.319(e).
Section 173.323. Paragraph (c)(1) is revised to require a tank test
pressure of at least 20.7 Bar (300 psi) for ethylene oxide no later
then 10 years after the effective date of this final rule.
Authorization for the use of a DOT 111A100W4 and 111J100W4 tank car is
removed.
Part 179
Section 179.1. In paragraph (c), the section reference
``Sec. 173.31'' is revised to read ``Sec. 180.507''.
[[Page 49069]]
Section 179.2. This section is amended by adding a definition for
``Tank car facility.''
Section 179.7. This section requires tank car facilities to have a
Quality Assurance Program (QAP). Paragraph (a) sets forth performance
standard for the program. Paragraphs (b)(1) through (b)(13) require
that the QAP have certain minimum requirements. The term ``Enhanced
visual imagery'' in paragraph (b)(10) is changed to read ``Optically-
aided visual inspection'' to correctly identify that the visual
inspection method is ``optically aided.'' Optically-aided visual
methods include the use of magnifiers, borescopes, fiberscopes, and
machine vision technology (e.g., a video digitizer that converts images
into digital form, and through image enhancement, image segmentation,
and feature extraction, the computer classifies objects within the
image). Paragraph (c) requires tank car facilities to ensure that only
personnel qualified to perform a particular nondestructive inspection
and test perform that operation. Paragraph (d) requires each tank car
facility to have written procedures, covering inspection, fabrication,
and repair operations as appropriate, for their employees. Paragraph
(e) cross-references the training requirements in Subpart H of Part
172. (Section 172.702 requires that a hazmat employer train each of its
hazmat employees.) Paragraph (f) specifies the compliance date by which
tank car facilities must have a QAP and written procedures in effect.
Section 179.16. This new section contains the tank-head puncture-
resistance requirements found in current Secs. 179.100-23 and 179.105-
5.
Section 179.18. This new section contains the thermal protection
requirements found in current Sec. 179.105-4(a), (b), and (c). A
requirement that the exterior of the tank car must be painted white in
proposed Sec. 179.18(d) is moved to Sec. 179.101-1, Note 4 in this
final rule. Editorial revisions are made to these requirements for
clarity and for consistency with other changes in this final rule.
Section 179.20. This new section contains bottom-discontinuity
protection requirements. For new tank cars, bottom-discontinuity
protection must conform to paragraphs E9.00 and E10.00 of the AAR
Specifications for Tank Cars, M-1002.
Section 179.22. New section 179.22 consolidates the marking
requirements contained in current Secs. 179.100-21, 179.105-8, 179.200-
25, and 179.203-3. Based on this consolidation, Secs. 179.100-21,
179.105-8, 179.200-25, and 179.203-3 are removed.
Section 179.100-4. This section is amended by removing the phrase
``except that a protective coating is not required when foam-in-place
insulation that adheres to the tank or jacket is applied'' at the end
of the first paragraph. This change is based on an AAR petition (P-
1050) to require protective coatings on the outside surface of the tank
shell and the inside surface of the jacket.
Section 179.100-21. The marking requirements contained in this
section are consolidated with other marking requirements in new
Sec. 179.22 and, as discussed earlier, Sec. 179.100-21 is removed.
Section 179.100-23. The head protection requirements contained in
this section are moved to Sec. 179.16(b), and, as discussed earlier,
Sec. 179.100-23 is removed.
Section 179.101-1. Certain editorial changes are made in
Sec. 179.101-1, Note 4, for clarity and consistency with other changes
made in this final rule. In the first sentence in Note 4, the section
reference ``Sec. 179.100-4,'' which addresses insulated tank cars, is
removed because Note 4 applies to non-insulated cars only. Note 4 is
revised to clarify that there is no need to paint the tank white when a
``thermal protection'' system is applied (consistent with current
Sec. 179.105-4(g) and proposed Sec. 179.16 (d)), and to remove a
requirement that tank cars in hydrogen fluoride service need to have a
dark colored band in the top platform and fitting area because hydrogen
fluoride is not a Class 2 (compressed gas) material. The last sentence
is also removed because it is not a mandatory requirement.
Section 179.103-1. Current paragraph (c), providing that a manway
may be located other than at the top of the tank is no longer valid
and, therefore, is removed and reserved.
Section 179.103-2. Current paragraph (a) containing manway cover
plate requirements is revised by removing the phrase ``may be of the
self-energizing type and''. This change would prohibit the construction
of tank cars with a self-energized manway located below the liquid
level of the lading.
Section 179.103-5. In current paragraph (a)(1), the first two
sentences authorizing the location of a self-energizing manway below
the liquid level of the tank is no longer valid and, therefore are
removed.
Section 179.105. Current Secs. 179.105 through 179.105-8 containing
special requirements for class DOT 105S, 105J, 111J, 112S, 112J, 112T,
114S, 114J, and 114T specification tank cars are removed because they
are unnecessary. The applicable requirements concerning head protection
and thermal protection are moved to Secs. 179.16, 179.18, and
Appendices A and B to Part 179, as appropriate. The marking
requirements are consolidated into Sec. 179.22. The requirement for
exterior tank color was moved to footnote 4 of the Sec. 179.101-1
table.
Section 179.200-4. This section is amended by removing the phrase
``except that a protective coating is not required when foam-in-place
insulation that adheres to the tank or jacket is applied'' at the end
of the first paragraph. This change is based on an AAR petition (P-
1050) to require protective coatings on the outside surface of the tank
shell and the inside surface of the jacket.
Section 179.200-25. The marking requirements contained in this
section are consolidated with other marking requirements in
Sec. 179.22, and, as discussed earlier, Sec. 179.200-25 is removed.
Section 179.200-27. The head protection requirements are
consolidated into Sec. 179.16. Therefore, current Sec. 179.200-27 is
removed.
Section 179.203. Current Secs. 179.203, 179.203-1, 179.203-2, and
179.203-3 containing special requirements for class DOT 111 tank cars
are unnecessary and are removed. The restriction in paragraph (c)
against the use of class DOT 111 tank cars built after March 1, 1984,
for the transportation of flammable gases or ethylene oxide is
incorporated into Secs. 173.314 and 173.323. The applicable head-
protection and thermal-protection requirements are consolidated into
Secs. 179.16 and 179.18, respectively. The marking requirements are
consolidated into Sec. 179.22.
Appendix A. The tank-head puncture-resistance test verification
requirements in Sec. 179.105-5 paragraphs (b) and (c) are moved to this
Appendix.
Appendix B. This appendix contains the thermal-protection test-
verification requirements found in current Sec. 179.105-4(d), (e) and
(f). These requirements are editorially revised for clarity.
Part 180
Subpart F of Part 180. This subpart contains the qualification and
maintenance requirements for tank cars.
Section 180.501. Paragraph (a) specifies the applicability of the
Subpart. Paragraph (b) specifies that any person who performs a
function required by Subpart F of Part 180 must perform that function
according to the regulations.
[[Page 49070]]
Section 180.503. This section defines certain terms used throughout
the subpart.
Section 180.505. This section requires each tank car facility
performing repair work to have a QAP based on requirements in
Sec. 179.7 for new car construction.
Section 180.507. This section contains the continuing
qualifications for existing tank cars that are no longer authorized for
new construction, such as a class DOT 113A175W tank car. Paragraph (a)
is essentially current Sec. 173.31(a)(1) except that it is revised to
include non-specification tank cars that are currently authorized for
the transportation of hazardous materials. Paragraphs (b)(1), (2), (3),
and (4) are current Sec. 173.31(a)(2), (8), (9), and (10).
Section 180.509. This section specifies the requirements for the
periodic inspection and testing of tank cars. Paragraph (a)(1) requires
each tank car facility to evaluate the tank car according to the
``Acceptable results of inspections and tests'' as prescribed in
Sec. 180.511. Paragraph (a)(2) requires marking each tank car passing a
periodic inspection and test to indicate the date it passed this review
and the due dates for the next inspection and test required in the new
Sec. 180.515. Paragraph (a)(3) requires a written report for each tank
car after it successfully passes an inspection and test. Paragraph (b)
specifies unusual conditions that may require an inspection and test of
tank cars. Paragraph (b)(1) requires an inspection and test if the tank
shows evidence of abrasion, corrosion, cracks, dents, distortions,
defects in welds, or any other condition unsafe for transportation.
Paragraph (b)(2) requires an inspection and test if the tank car was in
an accident and damaged to the extent that may adversely affect its
capability to retain its contents (e.g., large dent or gouge in the
tank shell). Paragraph (b)(3) requires an inspection and test if the
tank was involved in a fire. Paragraph (b)(4) requires an inspection
and test of either a single tank car or a design of tank cars operating
in an unsafe condition, if required by FRA, based on the existence of a
probable cause. Probable cause may include an inspection and test where
FRA discovers a crack in a welded area, a wheel burn, or a large dent
or bulge in the tank shell; it may also include a group of cars of a
given design if FRA discovers problems apparently related to cars of
that design.
Paragraph (c) specifies the frequency with which inspections and
tests must be performed on tank cars. Paragraph (c)(1) specifies the
requirements for the inspection and hydrostatic test of class DOT 107
tank cars and riveted tank cars. As noted above, the hydrostatic test
is still effective for these tank cars since it will detect loose
rivets and areas of metal distress. Paragraph (c)(2) requires an
inspection for thermal integrity of class DOT 113 tank cars in place of
the inspection and testing requirements in Subpart F of Part 180. This
paragraph cross-references the requirements in Sec. 173.319(e).
Paragraph (c)(3) specifies the inspection and test requirements for
fusion welded tank cars. The intervals would vary depending upon
whether or not the tank car was lined or coated and upon whether or not
the car was transporting materials corrosive to the tank. For linings
and coatings, this final rule requires a tank car facility to inspect
the lining or coating based on the inspection and test intervals and
techniques established by the lining or coating owner. The owner must
establish an inspection interval and test technique based on the
manufacturer's recommendations or the owner's knowledge of the life-
expectancy of the lining or coating.
Paragraph (d) specifies the manner for conducting a visual
inspection for each tank car. Paragraph (d)(1) requires an inspection
of the tank car internally and externally for abrasion, corrosion,
cracks, dents, distortions, defects in welds, or any other conditions
unsafe for transportation. Paragraph (d)(2) requires the inspection of
all piping, valves, fittings, and gaskets for corrosion and any other
condition unsafe for transportation. Paragraph (d)(3) requires an
inspection of the tank cars for missing or loose bolts, nuts, or other
elements. Paragraph (d)(4) requires an inspection of all closures on
the tank car for proper securement. The tank car facility would also
inspect the protective housings for proper securement. Paragraph (d)(5)
requires an inspection of the seats on excess flow valves. Paragraph
(d)(6) requires an inspection of the markings on the tank car for
legibility.
Paragraph (e) requires that a structural integrity inspection and
test shall include all transverse fillet welds greater than 0.64 cm
(0.25 inch) within four feet of the bottom longitudinal center line;
the termination of longitudinal fillet welds greater than 0.64 cm (0.25
inch) within four feet of the bottom longitudinal center line; and all
tank shell butt welds within two feet of the bottom longitudinal center
line using one or more nondestructive test methods. The term ``Enhanced
visual imagery'' is changed to read ``Optically-aided visual
inspection'' to correctly identify that the visual inspection method is
``optically aided.''
Paragraph (f) requires thickness measurements to determine that the
tank car is not below the minimum shell thickness.
Paragraph (g) specifies the allowable shell thickness reductions.
Paragraph (g)(1)(i) allows thickness reductions on carbon steel,
stainless steel, aluminum, nickel, and manganese-molybdenum steels.
Paragraph (g)(1)(ii) specifies the minimum shell and head thickness
reductions for uniform and localized areas and Note 5 of the table is
removed to disallow any reduction in the shell thickness for class DOT
111A tank cars transporting ethylene oxide. As discussed earlier, this
final rule prohibits the transportation of ethylene oxide in a class
DOT 111 tank car.
Paragraph (h)(1) requires the inspection of the safety systems on
the tank, such as thermal protection systems, tank-head puncture-
resistance systems, and coupler vertical restraint systems, to ensure
their integrity. Paragraph (h)(2) requires the inspection and test of
re-closing pressure relief devices (safety valves).
Paragraph (i) requires an inspection and test of tank cars with a
lining or coating on the tank car. The inspection interval is
determined by the owner based on the type of testing technique used,
and knowledge of the material and tank car, but cannot exceed 10 years.
Paragraph (j) requires a leakage pressure test of the tank car and
appurtenances.
Paragraph (k) allows the use of an alternative inspection and test
procedure provided the procedure is based on a damage-tolerance
evaluation, examined by the AAR Tank Car Committee, and approved by the
Associate Administrator for Safety FRA.
Paragraph (l) specifies the compliance date for the new inspection
and test requirements.
Section 180.511. This section specifies the acceptable results of
inspections and tests. Paragraph (a) establishes that an acceptable
visual inspection as one that shows no structural defect that may cause
the tank car to fail (including leak) before the next inspection and
test interval.
Paragraph (b) establishes that an acceptable structural integrity
inspection and test is one that shows no structural defect that may
initiate cracks or propagate cracks and cause the tank car to fail
before the next inspection and test interval.
Paragraph (c) establishes that an acceptable service life shell
thickness is one that shows no areas of the tank car
[[Page 49071]]
below the minimum shell or head thickness allowed in Sec. 180.509(g).
Paragraph (d) establishes that an acceptable safety system
inspection is one that shows the systems (e.g., a thermal protection
system) conform to Part 179.
Paragraph (e) establishes that an acceptable inspection and test
for lining and coatings as one that shows no holes or degraded areas.
Paragraph (f) establishes that an acceptable inspection and test
for a leakage pressure test as one that shows no indications of leakage
in any product piping, fitting, or closure.
Paragraph (g) establishes that an acceptable hydrostatic test, for
class DOT 107 tank cars and riveted tank cars, is one that shows no
leakage or deformations (i.e., distress) in the tank.
Section 180.513. This section specifies that tank car repairs must
conform to the requirements of Appendix R of AAR Specifications for
Tank Cars. As proposed in HM-175A, the introductory text becomes
paragraph (a), and Sec. 173.31 paragraph (f)(3) becomes Sec. 180.513
paragraph (b). Section 180.513(b) requires that, unless the exterior
tank car shell or interior tank car jacket has a protective coating,
when the complete tank car jacket is removed to effect a repair, the
exterior tank car shell and the interior tank car jacket must have a
protective coating applied to prevent the deterioration of the tank
shell and tank jacket.
Section 180.515. This section specifies the marking requirements
for tank cars after a successful tank inspection and test.
Section 180.517. This section specifies the reporting and record
retention requirements after a tank car has successfully completed its
required inspection and test. Paragraph (a) requires the tank car owner
to retain the certificate of construction of the tank car (AAR Form 4-
2) and related documentation certifying that the tank car conforms to
the specification. The owner shall retain the documents for the period
of ownership. Upon a change in ownership, Section 1.3.15 of AAR
Specifications for Tank Cars requires the transfer of these documents
to the new owner. Paragraph (b) specifies the inspection and test
reporting requirements.
Section 180.519. This section specifies the periodic test and
inspection requirements for multi-unit tank cars (e.g., class DOT 106
and 110 multi-unit tank cars).
V. Regulatory Analysis and Notices
A. Executive Order 12866 and DOT Regulatory Policies and Procedures
This final rule is considered a significant regulatory action under
section 3(f) of Executive Order 12866 and was reviewed by the Office of
Management and Budget. The rule is considered significant under the
Regulatory policies and Procedures of the Department of Transportation
(44 FR 11034) because it affects a significant segment of the tank car
industry. A regulatory evaluation is available for review in the
docket.
B. Executive Order 12612
This final rule has been analyzed in accordance with the principles
and criteria contained in Executive Order 12612 (``Federalism'').
Federal law expressly preempts State, local, and Indian tribe
requirements applicable to the transportation of hazardous material
that cover certain subjects and are not ``substantively the same'' as
the Federal requirements. 49 U.S.C. 5125(b)(1). These covered subjects
are:
(A) the designation, description, and classification of hazardous
material;
(B) the packing, repacking, handling, labeling, marking, and
placarding of hazardous material;
(C) the preparation, execution, and use of shipping documents
related to hazardous material and requirements respecting the number,
contents, and placement of those documents;
(D) the written notification, recording, and reporting of the
unintentional release in transportation of hazardous material; or
(E) the design, manufacturing, fabricating, marking, maintenance,
reconditioning, repairing, or testing of a packaging or a container
which is represented, marked, certified, or sold as qualified for use
in transporting hazardous material.
This final rule addresses the design, manufacturing, repairing, and
other requirements for packages represented as qualified for use in the
transportation of hazardous material. Therefore, this final rule
preempts State, local, or Indian tribe requirements that are not
``substantively the same'' as Federal requirements on these subjects.
Section 5125(b)(2) of Title 49 U.S.C. provides that when DOT issues a
regulation concerning any of the covered subjects after November 16,
1990, DOT must determine and publish in the Federal Register the
effective date of Federal preemption. The effective date may not be
earlier that the 90th day following the date of issuance of the final
rule and no later than two years after the date of issuance. RSPA has
determined that the effective date of Federal preemption of this final
rule will be 90 days after publication in the Federal Register.
Because RSPA lacks discretion in this area, preparation of a
federalism assessment is not warranted.
C. Regulatory Flexibility Act
I certify that this final rule will not have a significant economic
impact on a substantial number of small entities. The entities affected
by the rule are involved in tank car leasing, maintenance, repair and
use. There are no direct or indirect adverse economic impacts for small
units of government, businesses, or other organizations.
D. Paperwork Reduction Act
The requirements for information collection have been approved by
the Office of Management and Budget (OMB) under the provision of the
Paperwork Reduction Act of 1980 (Pub. L. 95-511) under OMB control
number 2137-0559.
E. Regulation Identifier Number (RIN)
A regulation identifier number (RIN) is assigned to each regulatory
action listed in the Unified Agenda of Federal Regulations. The
Regulatory Information Service Center publishes the Unified Agenda in
April and October of each year. The RIN numbers contained in the
heading of this document can be used to cross-reference this action
with the Unified Agenda.
List of Subjects
49 CFR Part 171
Exports, Hazardous materials transportation, Hazardous waste,
Imports, Incorporation by reference, Reporting and recordkeeping
requirements.
49 CFR Part 172
Hazardous materials transportation, Hazardous waste, Labels,
Markings, Packaging and containers, Reporting and recordkeeping
requirements.
49 CFR Part 173
Hazardous materials transportation, Incorporation by reference,
Packaging and containers, Radioactive materials, Reporting and
recordkeeping requirements, Uranium.
49 CFR Part 179
Hazardous materials transportation, Incorporation by reference,
Railroad safety, Reporting and recordkeeping requirements.
[[Page 49072]]
49 CFR Part 180
Hazardous materials transportation, Incorporation by reference,
Motor carriers, Motor vehicle safety, Packaging and containers,
Railroad safety, Reporting and recordkeeping requirements.
In consideration of the foregoing, 49 CFR Chapter I is amended as
follows:
PART 171--GENERAL INFORMATION, REGULATIONS, AND DEFINITIONS
1. The authority citation for part 171 continues to read as
follows:
Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.
Sec. 171.7 [Amended]
2. In Sec. 171.7, in paragraph (a)(3) Table, the following changes
are made:
a. Under the Association of American Railroads, for the entry ``AAR
Manual of Standards and Recommended Practices, Section C-Part III,
Specifications for Tank Cars, Specification M-1002, September, 1992''
in column 2, the references are revised to read ``173.31; 174.63;
179.6; 179.7; 179.12; 179.16; 179.20; 179.22; 179.100; 179.101;
179.102; 179.103; 179.200; 179.201; 179.220; 179.300; 179.400; 180.509;
180.513; 180.515; 180.517.''.
b. Under the Association of American Railroads, for the entry ``AAR
Specifications for Design, Fabrication and Construction of Freight
Cars, Volume 1, 1988'' in column 2, the reference is revised to read
``179.16.''.
c. Under the Compressed Gas Association, Inc., for the entry ``CGA
Pamphlet C-6, Standards for Visual Inspection of Compressed Gas
Cylinders, 1984'' in column 2, the reference is revised to read
``173.34; 180.519.''.
PART 172--HAZARDOUS MATERIALS TABLE, SPECIAL PROVISIONS, HAZARDOUS
MATERIALS COMMUNICATIONS, EMERGENCY RESPONSE INFORMATION, AND
TRAINING REQUIREMENTS
3. The authority citation for part 172 continues to read as
follows:
Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.
Sec. 172.101 [Amended]
4. In Sec. 172.101, in the Hazardous Materials Table, the following
changes are made:
a. For the entries ``Benzyl chloride'', ``Fluorosulfonic acid'',
and ``Titanium tetrachloride'', in Column (7), Special Provision
``B41,'' is removed.
b. For the entries ``Carbon dioxide, refrigerated liquid'' and
``Vinyl fluoride inhibited'', in Column (7), Special Provision ``B43''
is removed.
c. For the entry ``Hydrogen chloride, refrigerated liquid'', in
Column (7), Special Provision ``, B43'' is removed.
d. For the entry ``Ethyl methyl ether'', in column (7), Special
Provision ``B63'' is removed.
e. For the entry ``Ethyl chloride'', in column (7), Special
Provision ``B63,'' is removed.
Sec. 172.102 [Amended]
5. In Sec. 172.102, in paragraph (c)(3), the following changes are
made:
a. Special Provision ``B41'' is removed.
b. Special Provision ``B43'' is removed.
c. Special Provision ``B63'' is removed.
d. Special Provision ``B64'' is amended by revising the section
reference ``Sec. 179.105-5'' to read ``Sec. 179.16''.
e. Special Provision ``B79'' is amended by revising the section
references ``Secs. 179.105-4 and 179.105-5'' to read ``Secs. 179.16 and
179.18''.
PART 173--SHIPPERS--GENERAL REQUIREMENTS FOR SHIPMENTS AND
PACKAGINGS
6. The authority citation for part 173 continues to read as
follows:
Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.
7. Section 173.31 is revised to read as follows:
Sec. 173.31 Use of tank cars.
(a) General. (1) No person may offer a hazardous material for
transportation in a tank car unless the tank car meets the applicable
specification and packaging requirements of this subchapter or, when
this subchapter authorizes the use of an non-DOT specification tank
car, the applicable specification to which the tank was constructed.
(2) Tank cars and appurtenances may be used for the transportation
of any commodity for which they are authorized in this part and
specified on the certificate of construction (AAR Form 4-2 or by
addendum on Form R-1). See Sec. 179.5 of this subchapter. Transfer of a
tank car from one specified service on its certificate of construction
to another may be made only by the owner or with the owner's
authorization. A tank car proposed for a commodity service other than
specified on its certificate of construction must be approved for such
service by the AAR's Tank Car Committee.
(3) No person may fill a tank car overdue for periodic inspection
with a hazardous material and then offer it for transportation. Any
tank car marked as meeting a DOT specification and any non-
specification tank car transporting a hazardous material must have a
periodic inspection and test conforming to Subpart F of Part 180 of
this subchapter.
(4) No railroad tank car, regardless of its construction date, may
be used for the transportation in commerce of any hazardous material
unless the air brake equipment support attachments of such tank car
conform to the standards for attachments set forth in Secs. 179.100-16
and 179.200-19 of this subchapter.
(5) No railroad tank car, regardless of its construction date, may
be used for the transportation in commerce of any hazardous material
with a self-energized manway located below the liquid level of the
lading.
(6) Unless otherwise specifically provided in this part:
(i) When this subchapter designates a specific specification tank
car, the same class tank car with a higher marked test pressure also
may be used.
(ii) When the tank car specification delimiter is an ``A,''
offerors may also use tank cars with a delimiter ``S,'' ``J'' or ``T''.
(iii) When the tank car specification delimiter is an ``S,''
offerors may also use tank cars with a delimiter ``J'' or ``T''.
(iv) When a tank car specification delimiter is a ``T'' offerors
may also use tank cars with a delimiter of ``J''.
(v) When a tank car specification delimiter is a ``J'', offerors
may not use a tank car with any other specification delimiter.
(b) Safety systems--(1) Coupler vertical restraint. Each tank car
conforming to a DOT specification and any other tank car used for
transportation of a hazardous material must be equipped with a coupler
vertical restraint system that meets the requirements of Sec. 179.14 of
this subchapter.
(2) Pressure relief devices. (i) Pressure relief devices on tank
cars must conform to Part 179 of this subchapter.
(ii) Except for shipments of chloroprene, inhibited, in class DOT
115 tank cars, tank cars used for materials meeting the definition for
Division 6.1 liquid, Packing Group I or II, Class 2 materials, or Class
3 or 4 liquids, must have self-closing pressure relief devices.
However, a tank car built before January 1, 1991, and equipped with a
non-closing pressure relief device may be used to transport a Division
6.1 or Class 4 liquid if the liquid is not poisonous by inhalation.
Unless otherwise specifically provided in this
[[Page 49073]]
subchapter, frangible discs may not have breather holes.
(3) Tank-head puncture-resistance requirements. The following tank
cars must have a tank-head puncture-resistance system that conforms to
the requirements in Sec. 179.16 of this subchapter, or to the
corresponding requirements in effect at the time of installation:
(i) Tank cars transporting a Class 2 material.
(ii) Tank cars constructed from aluminum or nickel plate that are
used to transport hazardous material.
(iii) Except as provided in paragraph (b)(3)(iv) of this section,
tank cars not requiring a tank-head puncture-resistance system prior to
July 1, 1996, must have a tank-head puncture-resistance system
installed no later than July 1, 2006.
(iv) Class DOT 105A tank cars built prior to September 1, 1981,
having a tank capacity less than 70 kl (18,500 gallons), and used to
transport a Division 2.1 (flammable gas) material, must have a tank-
head puncture-resistant system installed no later than July 1, 2001.
(4) Thermal protection requirements. The following tank cars must
have thermal protection that conforms to the requirements of
Sec. 179.18 of this subchapter:
(i) Tank cars transporting a Class 2 material, except for class DOT
105A tank cars transporting chlorine, carbon dioxide refrigerated
liquid, or nitrous oxide refrigerated liquid, and class DOT 106, 107A,
110, and 113 tank cars.
(ii) Tank cars not requiring thermal protection prior to July 1,
1996, must conform to this section no later than July 1, 2006.
(5) Bottom-discontinuity protection requirements. No person may
offer for transportation a hazardous material in a tank car unless the
tank car has bottom-discontinuity protection that conforms to the
requirements of E9.00 and E10.00 of the AAR Specifications for Tank
Cars. Tank cars not requiring bottom-discontinuity protection under the
terms of Appendix Y of the AAR Specifications for Tank Cars as of July
1, 1996, must conform to these requirements no later than July 1, 2006.
Tank cars modified before July 1, 1996, may conform to the bottom-
discontinuity protection requirements of Appendix Y of the 1992 edition
of the AAR Specifications for Tank Cars.
(6) Scheduling of modifications and progress reporting. The date of
conformance for the continued use of tank cars subject to paragraphs
(b)(3), (b)(4), (b)(5), (e)(2), and (f) of this section and
Secs. 173.314(j) and 173.323(c)(1) is subject to the following
conditions and limitations.
(i) Each tank car owner shall modify, reassign, retire, or remove
at least 50 percent of their in-service tank car fleet within the first
half of the compliance period and the remainder of their in-service
tank car fleet during the second half of the compliance period.
(ii) Before July 1 of each year, each owner shall submit to the
Associate Administrator for Safety, FRA (Attention: RRS-12) a progress
report that shows the reporting mark of each tank car, the status of
each tank car during the previous year, and the total number of those
tank cars modified reassigned, retired, or removed the previous year.
(c) Tank car test pressure. A tank car used for the transportation
of a hazardous material must have a tank test pressure equal to or
greater than the greatest of the following:
(1) Except for shipments of carbon dioxide, anhydrous hydrogen
chloride, vinyl fluoride, ethylene, or hydrogen, 133 percent of the sum
of lading vapor pressure at the reference temperature of 46 deg.C (115
deg.F) for non-insulated tank cars or 41 deg.C (105 deg.F) for
insulated tank cars plus static head, plus gas padding pressure in the
vacant space of a tank car;
(2) 133 percent of the maximum loading or unloading pressure,
whichever is greater;
(3) 20.7 Bar (300 psi) for materials that are poisonous by
inhalation;
(4) The minimum pressure prescribed by the specification in Part
179 of this subchapter; or
(5) The minimum test pressure prescribed for the specific hazardous
material in the applicable packaging section in Subpart F or G of this
Part.
(d) Examination before shipping. (1) No person may offer for
transportation a tank car containing a hazardous material or a residue
of a hazardous material unless that person determines that the tank car
is in proper condition and safe for transportation. As a minimum, each
person offering a tank car for transportation must perform an external
visual inspection that includes:
(i) Except where insulation or a thermal protection system
precludes an inspection, the tank shell and heads for abrasion,
corrosion, cracks, dents, distortions, defects in welds, or any other
condition that makes the tank car unsafe for transportation;
(ii) The piping, valves, fittings, and gaskets for corrosion,
damage, or any other condition that makes the tank car unsafe for
transportation;
(iii) For missing or loose bolts, nuts, or elements that make the
tank car unsafe for transportation;
(iv) All closures on tank cars and determine that the closures and
all fastenings securing them are properly tightened in place by the use
of a bar, wrench, or other suitable tool;
(v) Protective housings for proper securement;
(vi) The pressure relief device, including a careful inspection of
the frangible disc in non-closing pressure relief devices, for
corrosion or damage that may alter the intended operation of the
device;
(vii) Each tell-tale indicator after filling and prior to
transportation to ensure the integrity of the frangible disc;
(viii) The external thermal protection system, tank head puncture
resistance system, coupler vertical restraint system, and other safety
systems for conditions that make the tank car unsafe for
transportation;
(ix) The required markings on the tank car for legibility; and
(x) The periodic inspection date markings to ensure that the
inspection and test intervals are within the prescribed intervals.
(2) Closures on tank cars are required, under this subchapter, to
be designed and closed so that under conditions normally incident to
transportation, including the effects of temperature and vibration,
there will be no identifiable release of a hazardous material to the
environment. In any action brought to enforce this section, the lack of
securement of any closure to a tool-tight condition, detected at any
point, will establish a rebuttable presumption that a proper inspection
was not performed by the offeror of the car. That presumption may be
rebutted only by evidence establishing that the car was subjected to
abnormal treatment, e.g., a derailment or vandalism.
(e) Special requirements for materials poisonous by inhalation--(1)
Interior heater coils. Tank cars used for materials poisonous by
inhalation may not have interior heater coils.
(2) Tank car specifications. Except as otherwise provided in this
subchapter, tank cars used for materials poisonous by inhalation must
conform to at least a DOT 105S300W, 105S300ALW, 112J340W, or 114J340W
specification. Hazardous materials not requiring the use of a class DOT
105S300W, 105S300ALW, 112J340W, or 114J340W tank car prior to July 1,
1996, must be transported in one of these specifications no later than
July 1, 2006.
(f) Special requirements for hazardous substances. (1) Before July
1, 2006, each tank car used for transportation of a
[[Page 49074]]
hazardous substance listed in paragraph (f)(2) of this section must
conform to DOT 105S200W, DOT 112S200W with an 11-gauge steel jacket,
DOT 112S340W, or DOT 112S200W constructed from AAR steel specification
TC-128, normalized.
(2) List of hazardous substances. Hazardous substances for which
the provisions of this paragraph (f) apply are as follows:
Aldrin
Allyl chloride
alpha-BHC
beta-BHC
delta-BHC
gamma-BHC
Bis(2-chloroethyl) ether
Bromoform
Carbon tetrachloride
Chlordane
p-Chloroaniline
Chlorobenzene
Chlorobenzilate
p-Chloro-m-cresol
2-Chloroethyl vinyl ether
Chloroform
2-Chloronapthalene
o-Chlorophenol
3-Chloropropionitrile
DDE
DDT
1,2-Dibromo-3-chloropropane
m-Dichlorobenzene
o-Dichlorobenzene
p-Dichlorobenzene
3,3'-Dichlorobenzidine
1,4-Dichloro-2-butene
1,1-Dichloroethane
1,2-Dichloroethane
1,1-Dichloroethylene
Dichloroisopropyl ether
Dichloromethane @
2,4-Dichlorophenol
2,6-Dichlorophenol
1,2-Dichloropropane
1,3-Dichloropropene
Dieldrin
alpha-Endosulfan
beta-Endosulfan
Endrin
Endrin aldehyde
Heptachlor
Heptachlor epoxide
Hexachlorobenzene
Hexachlorobutadiene
Hexachloroethane
Hexachlorophene
Hexachloropropene
Isodrin
Kepone
Methoxychlor
4,4'-Methylenebis(2-chloroaniline)
Methylene bromide
Pentachlorobenzene
Pentachloroethane
Pentachloronitrobenzene (PCNB)
Pentachlorophenol
Polychlorinated biphenyls (PCBs)
Pronamide
Silvex (2,4,5-TP)
2,4,5-T
TDE
1,2,4,5-Tetrachlorobenzene
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)
Tetrachloroethane
Tetrachloroethylene
2,3,4,6-Tetrachlorophenol
Toxaphene
1,2,4-Trichlorobenzene
1,1,1-Trichloroethane
1,1,2-Trichloroethane
Trichloroethylene
2,4,5-Trichlorophenol
2,4,6-Trichlorophenol
Tris(2,3-dibromopropyl) phosphate
8. In Sec. 173.314, the section heading and paragraph (c) are
revised, and paragraphs (j) through (o) are added to read as follows:
Sec. 173.314 Compressed gases in tank cars and multi-unit tank cars.
* * * * *
(c) Authorized gases, filling limits for tank cars. A compressed
gas in a tank car or a multi-unit tank car must be offered for
transportation in accordance with Sec. 173.31 and this section. The
named gases must be loaded and offered for transportation in accordance
with the following table:
----------------------------------------------------------------------------------------------------------------
Outage and filling
Proper shipping name limits (see note 1) Authorized tank car class
----------------------------------------------------------------------------------------------------------------
Ammonia, anhydrous, or ammonia solutions > 50 percent Note 2.............. 105, 112, 114.
ammonia.
Note 3.............. 106.
Ammonia solutions with > 35 percent, but 50 Note 3.............. 105, 109, 112, 114.
percent ammonia by mass.
Argon, compressed...................................... Note 4.............. 107.
Boron trichloride...................................... Note 3.............. 105, 106.
Carbon dioxide, refrigerated liquid.................... Note 5.............. 105.
Chlorine............................................... Note 6.............. 105.
125................. 106.
Chlorine trifluoride................................... Note 3.............. 106, 110.
Chlorine pentafluoride................................. Note 3.............. 106, 110.
Dimethyl ether......................................... Note 3.............. 105, 106, 110.
Dimethylamine, anhydrous............................... Note 3.............. 105, 106, 112.
Dinitrogen tetroxide, inhibited........................ Note 3.............. 105, 106, 110.
Division 2.1 materials not specifically identified in Note 3.............. 105, 106, 110, 112, 114.
this table.
Division 2.2 materials not specifically identified in Note 3.............. 105, 106, 109, 110, 112, 114.
this table.
Division 2.3 Zone A materials not specifically None................ See Sec. 173.245.
identified in this table.
Division 2.3 Zone B materials not specifically Note 3.............. 105, 106, 110, 112, 114.
identified in this table.
Division 2.3 Zone C materials not specifically Note 3.............. 105, 106, 110, 112, 114.
identified in this table.
Division 2.3 Zone D materials not specifically Note 3.............. 105, 106, 109, 110, 112, 114.
identified in this table.
Ethylamine............................................. Note 3.............. 105, 106, 110, 112, 114.
Helium, compressed..................................... Note 4.............. 107.
Hydrogen............................................... Note 4.............. 107.
Hydrogen chloride, refrigerated liquid................. Note 7.............. 105.
Hydrogen sulphide, liquified........................... 68.................. 106.
Methyl bromide......................................... Note 3.............. 105, 106.
Methyl chloride........................................ Note 3.............. 105, 106, 112.
Methyl mercaptan....................................... Note 3.............. 105, 106.
Methylamine, anhydrous................................. Note 3.............. 105, 106, 112.
Nitrogen, compressed................................... Note 4.............. 107.
Nitrosyl chloride...................................... 124................. 105.
110................. 106.
[[Page 49075]]
Nitrous oxide, refrigerated liquid..................... Note 5.............. 105.
Oxygen, compressed..................................... Note 4.............. 107.
Phosgene............................................... Note 3.............. 106.
Sulfur dioxide, liquified.............................. 125................. 105, 106, 110.
Sulfuryl fluoride...................................... 120................. 105.
Vinyl fluoride, inhibited.............................. Note 8.............. 105.
----------------------------------------------------------------------------------------------------------------
Notes:
1. The percent filling density for liquefied gases is hereby defined as the ratio of the mass of gas in the tank
to the mass of water the tank will hold. For determining the water capacity of the tank in kilograms, the mass
of one liter (0.264 gallons) of water at 15.55 deg.C (60 deg.F.) in air is 1 kg (2.204 pounds).
2. The liquefied gas must be so loaded so that the outage is at least two percent of the total capacity of the
tank at the reference temperature of 46 deg.C (115 deg.F.) for non-insulated tanks and 41 deg.C (105
deg.F.) for insulated tanks.
3. The requirements of Sec. 173.24b(a) apply.
4. The gas pressure at 54.44 deg.C (130 deg.F.) in any non-insulated tank car may not exceed 7/10 of the
marked test pressure, except that a tank may be charged with helium to a pressure 10 percent in excess of the
marked maximum gas pressure at 54.44 deg.C (130 deg.F.) of each tank.
5. The liquid portion of the gas at -17.77 deg.C (0 deg.F.) must not completely fill the tank.
6. The maximum permitted filling density is 125 percent. The quantity of chlorine loaded into a single unit-tank
car may not be loaded in excess of the normal lading weights nor in excess of 81.65 Mg (90 tons).
7. 89 percent maximum to 80.1 percent minimum at a test pressure of 6.2 Bar (90 psi).
8. 59.6 percent maximum to 53.6 percent minimum at a test pressure of 7.2 Bar (105 psi).
* * * * *
(j) Special requirements for materials having a primary or
secondary Division 2.1 (flammable gas) hazard. For single unit tank
cars, interior pipes of loading and unloading valves, sampling devices,
and gauging devices with an opening for the passage of the lading
exceeding 1.52 mm (0.060 inch) diameter must be equipped with excess
flow valves. For single unit tank cars constructed before January 1,
1972, gauging devices must conform to this paragraph by no later than
July 1, 2006. The protective housing cover must be provided with an
opening, with a weatherproof cover, above each safety relief valve that
is concentric with the discharge of the safety relief valve and that
has an area at least equal to the valve outlet area. Class DOT 109 tank
cars and tank cars manufactured from aluminum or nickel plate are not
authorized.
(k) Special requirements for chlorine. Tank cars built after
September 30, 1991, must have an insulation system consisting of 5.08
cm (2 inches) glass fiber placed over 5.08 cm (2 inches) of ceramic
fiber. Tank cars must have excess flow valves on the interior pipes of
liquid discharge valves. Tank cars constructed to a DOT 105A500W
specification may be marked as a DOT 105A300W specification with the
size and type of safety relief valves required by the marked
specification.
(l) Special requirements for hydrogen sulphide. Each multi-unit
tank car must be equipped with adequate safety relief devices of the
fusible plug type having a yield temperature not over 76.66 deg.C (170
deg.F.), and not less than 69.44 deg.C (157 deg.F.). Each device
must be resistant to extrusion of the fusible alloy and leak tight at
55 deg.C (130 deg.F.). Each valve outlet must be sealed by a threaded
solid plug. In addition, all valves must be protected by a metal cover.
(m) Special requirements for nitrosyl chloride. Single unit tank
cars and their associated service equipment, such as venting, loading
and unloading valves, and safety relief valves, must be made of metal
or clad with a material that is not subject to rapid deterioration by
the lading. Multi-unit tank car tanks must be nickel-clad and have
safety relief devices incorporating a fusible plug having a yield
temperature of 79.44 deg.C (175 deg.F.). Safety relief devices must
be vapor tight at 54.44 deg.C (130 deg.F.).
(n) Special requirements for hydrogen chloride. Each tank car must
be equipped with one or more safety relief devices. The discharge
outlet for each safety relief device must be connected to a manifold
having a non-obstructed discharge area of at least 1.5 times the total
discharge area of the safety relief devices connected to the manifold.
All manifolds must be connected to a single common header having a non-
obstructed discharge pointing upward and extending above the top of the
car. The header and the header outlet must each have a non-obstructed
discharge area at least equal to the total discharge area of the
manifolds connected to the header. The header outlet must be equipped
with an ignition device that will instantly ignite any hydrogen
discharged through the safety relief device.
(o) Special requirements for carbon dioxide, refrigerated liquid
and nitrous oxide, refrigerated liquid. Each tank car must have an
insulation system so that the thermal conductance is not more than
0.613 kilojoules per hour, per square meter, per degree Celsius (0.03
B.t.u. per square foot per hour, per degree Fahrenheit) temperature
differential. Each tank car must be equipped with one safety relief
valve set to open at a pressure not exceeding 75 percent of the tank
test pressure and one frangible disc design to burst at a pressure less
than the tank test pressure. The discharge capacity of each safety
relief device must be sufficient to prevent building up of pressure in
the tank in excess of 82.5 percent of the test pressure of the tank.
Tanks must be equipped with two regulating valves set to open at a
pressure not to exceed 24.1 Bar (350 psi) on DOT 105A500W tanks and at
a pressure not to exceed 27.6 Bar (400 psi) on DOT 105A600W tanks. Each
regulating valve and safety relief device must have its final discharge
piped to the outside of the protective housing.
9. In Sec. 173.319, new paragraph (e) is added to read as follows:
Sec. 173.319 Cryogenic liquids in tank cars.
* * * * *
(e) Special requirements for class DOT 113 tank cars. (1) A class
DOT-113 tank car need not be periodically pressure tested; however,
each shipment must be monitored to determine the average daily pressure
rise in the tank car. If the average daily pressure rise during any
shipment exceeds 0.2 Bar (3 psi) per day, the tank must be tested for
thermal integrity prior to any subsequent shipment.
(2) Thermal integrity test. When required by paragraph (e)(1) of
this section, either of the following thermal integrity tests may be
used:
(i) Pressure rise test. The pressure rise in the tank may not
exceed 0.34 Bar (5 psi) in 24 hours. When the pressure rise test is
performed, the absolute pressure in the annular space of the loaded
tank car may not exceed 75 microns of
[[Page 49076]]
mercury at the beginning of the test and may not increase more than 25
microns during the 24-hour period; or
(ii) Calculated heat transfer rate test. The insulation system must
be performance tested as prescribed in Sec. 179.400-4 of this
subchapter. When the calculated heat transfer rate test is performed,
the absolute pressure in the annular space of the loaded tank car may
not exceed 75 microns of mercury at the beginning of the test and may
not increase more than 25 microns during the 24-hour period. The
calculated heat transfer rate in 24 hours may not exceed:
(A) 120 percent of the appropriate standard heat transfer rate
specified in Sec. 179.401-1 of this subchapter, for DOT-113A60W and
DOT-113C120W tank cars;
(B) 122.808 joules (0.1164 Btu/day/lb.) of inner tank car water
capacity, for DOT-113A175W tank cars;
(C) 345.215 joules (0.3272 Btu/day/lb.) of inner tank car water
capacity, for DOT-113C60W and 113D60W tank cars; or
(D) 500.09 joules (0.4740 Btu/day/lb.) of inner tank car water
capacity, for DOT-113D120W tank cars.
(3) A tank car that fails a test prescribed in paragraph (e)(2) of
this section must be removed from hazardous materials service. A tank
car removed from hazardous materials service because it failed a test
prescribed in paragraph (e)(2) of this section may not be used to
transport a hazardous material unless the tank car conforms to all
applicable requirements of this subchapter.
(4) Each frangible disc must be replaced with a new frangible disc
every 12 months, and the replacement date must be marked on the car
near the pressure relief valve information.
(5) Pressure relief valves and alternate pressure relief valves
must be tested every five years. The start-to-discharge pressure and
vapor tight pressure requirements for the pressure relief valves must
be as specified in Sec. 179.401-1 of this subchapter. The alternate
pressure relief device values specified in Sec. 179.401-1 of this
subchapter for a DOT-113C120W tank car apply to a DOT-113D120W tank
car.
Sec. 173.319 [Amended]
10. In addition, in Sec. 173.319, in paragraph (a)(4)(iii), the
parenthetical reference ``(see Sec. 173.31(c)(13))'' is removed.
11. In Sec. 173.323, paragraph (c)(1) is revised to read as
follows:
Sec. 173.323 Ethylene oxide.
* * * * *
(c) * * *
(1) Tank cars. Class DOT 105J tank cars: Notwithstanding the
requirements of Sec. 173.31(c), each tank car must have a tank test
pressure of at least 20.7 Bar (300 psi) no later than July 1, 2006.
* * * * *
PART 179--SPECIFICATIONS FOR TANK CARS
2. The authority citation for part 179 continues to read as
follows:
Authority: 49 App. U.S.C. 5101-5127; 49 CFR 1.53.
Sec. 179.1 [Amended]
13. In Sec. 179.1, in paragraph (c), the section reference
``Sec. 173.31'' is revised to read ``Sec. 180.507''.
14. In Sec. 179.2, paragraph (a)(10) is redesignated as paragraph
(a)(11) and a new paragraph (a)(10) is added to read as follows:
Sec. 179.2 Definitions and abbreviations.
(a) * * *
(10) Tank car facility means an entity that manufactures, repairs,
inspects, or tests a tank car to ensure that the tank car conforms to
this part and subpart F of part 180 of this subchapter, that alters the
certificate of construction of the tank car, that ensures the
continuing qualification of a tank car by performing a function
prescribed in parts 179 or 180 of this subchapter, or that makes any
representation indicating compliance with one or more of the
requirements of parts 179 or 180 of this subchapter.
* * * * *
15. Section 179.7 is added to subpart A to read as follows:
Sec. 179.7 Quality assurance program.
(a) At a minimum, each tank car facility shall have a quality
assurance program, approved by AAR, that--
(1) Ensures the finished product conforms to the requirements of
the applicable specification and regulations of this subchapter;
(2) Has the means to detect any nonconformity in the manufacturing,
repair, or testing of the tank car; and
(3) Prevents non-conformities from recurring.
(b) At a minimum, the quality assurance program must have the
following elements
(1) Statement of authority and responsibility for those persons in
charge of the quality assurance program.
(2) An organizational chart showing the interrelationship between
managers, engineers, purchasing, construction, inspection, testing, and
quality control personnel.
(3) Procedures to ensure that the latest applicable drawings,
design calculations, specifications, and instructions are used in
manufacture, inspection, testing, and repair.
(4) Procedures to ensure that the fabrication and construction
materials received are properly identified and documented.
(5) A description of the manufacturing, inspection, and testing
program so that an inspector can determine specific inspection and test
intervals.
(6) Monitoring and control of processes and product characteristics
during production.
(7) Procedures for correction of imperfections.
(8) Provisions indicating that the requirements of the AAR
Specifications for Tank Cars, Specification M-1002, apply.
(9) Qualification requirements of personnel performing ultrasonic,
radiographic, dye penetrant, magnetic particle, or other non-
destructive inspections and tests.
(10) Qualification requirements of personnel performing optically
aided visual inspections (including fiber optic, borescope, and video-
image-scope systems). Under these requirements, the examiner must have
the capability to consistently and repetitively find flaws under test
conditions. Furthermore, the requirements must include visual acuity
criteria where detectability (minimum size of a flaw that an examiner
can find); resolution (minimum distance at which two flaws may be seen
separately); and contrast sensitivity (minimum detectable thickness
change (convolutions) over a surface area) further define the
qualifications of the examiner.
(11) Procedures for evaluating the inspection and test technique
employed, including the accessibility of the area and the sensitivity
of the inspection and test technique and minimum detectable crack
length.
(12) Procedures for the periodic calibration and measurement of
inspection and test equipment.
(13) A system for the maintenance of records, inspections, tests,
and the interpretation of inspection and test results.
(c) Each tank car facility shall ensure that only personnel
qualified for each non-destructive inspection and test perform that
particular operation.
(d) Each tank car facility shall establish written procedures for
their employees to ensure that the work performed on the tank car
conforms to the specification and AAR approval for the tank car.
(e) Each tank car facility shall train its employees in accordance
with Subpart
[[Page 49077]]
H of part 172 of this subchapter on the program and procedures
specified in paragraph (b) of this section to ensure quality.
(f) Date of conformance. After July 1, 1998, no tank car facility
may manufacture, repair, inspect, or test tank cars subject to
requirements of this subchapter, unless it is operating in conformance
with a quality assurance program and written procedures required by
paragraphs (a) and (b) of this section.
16. Section 179.16 is added to subpart B to read as follows:
Sec. 179.16 Tank-head puncture-resistance systems.
(a) Performance standard. When the regulations in this subchapter
require a tank-head puncture-resistance system, the system shall be
capable of sustaining, without any loss of lading, coupler-to-tank-head
impacts at relative car speeds of 29 km/hour (18 mph) when:
(1) The weight of the impact car is at least 119,295 kg (263,000
pounds);
(2) The impacted tank car is coupled to one or more backup cars
that have a total weight of at least 217,724 kg (480,000 pounds) and
the hand brake is applied on the last ``backup'' car; and
(3) The impacted tank car is pressurized to at least 6.9 Bar (100
psi).
(b) Compliance with the requirements of paragraph (a) of this
section shall be verified by full-scale testing according to Appendix A
of this part or by installing full-head protection (shields) or full
tank-head jackets on each end of the tank car conforming to the
following
(1) The tank-head puncture-resistance system must be at least 1.27
cm (0.5 inch) thick, shaped to the contour of the tank head and made
from steel having a tensile strength greater than 379.21 N/mm\2\
(55,000 psi).
(2) The design and test requirements of the tank-head puncture-
resistance system must meet the impact test requirements of Section 5.3
of the AAR Specifications for Tank Cars.
(3) The workmanship must meet the requirements of Section C, Part
II, Chapter 5 of the AAR Specifications for Design, Fabrication, and
Construction of Freight Cars.
17. Section 179.18 is added to subpart B to read as follows:
Sec. 179.18 Thermal protection systems.
(a) Performance standard. When the regulations in this subchapter
require thermal protection on a tank car, the tank car must have
sufficient thermal resistance so that there will be no release of any
lading within the tank car, except release through the safety relief
valve, when subjected to:
(1) A pool fire for 100 minutes; and
(2) A torch fire for 30 minutes.
(b) Thermal analysis. (1) Compliance with the requirements of
paragraph (a) of this section shall be verified by modeling the fire
effects on the entire surface of the tank car according to the
procedures outlined in ``Temperatures, Pressures and Liquid Levels of
Tank Cars Engulfed in Fires,'' DOT/FRA/OR&D-84/08.11, (1984), Federal
Railroad Administration, Washington D.C. (available from National
Technical Information Service, Springfield, VA 22161), or other
procedure approved by the AAR Committee on Tank Cars. The analysis must
also consider the fire effects on and the heat flux through tank
discontinuities, protective housings, underframes, metal jackets,
insulation, and thermal protection. A complete record of each analysis
shall be made, retained and, upon request, made available for
inspection and copying by an authorized representative of the
Department.
(2) When the analysis shows the thermal resistance of the tank car
does not conform to paragraph (a) of this section, the thermal
resistance of the tank car must be increased by using a system listed
by the Department under paragraph (c) of this section or by testing an
unlisted system and verifying it according to appendix B of this part.
(c) Systems that no longer require test verification. The
Department maintains a list of thermal protection systems that comply
with the requirements of appendix B of this part and that no longer
require test verification. Information necessary to equip tank cars
with one of these systems is available in the Dockets Unit, Research
and Special Programs Administration, 400 Seventh Street, SW.,
Washington, D.C. 20590-0001.
18. Section 179.20 is added to subpart B to read as follows:
Sec. 179.20 Service equipment; protection systems.
If an applicable tank car specification authorizes location of
filling or discharge connections in the bottom shell, the connections
must be designed, constructed, and protected according to paragraphs
E9.00 and E10.00 of the AAR Specifications for Tank Cars, M-1002.
19. Section 179.22 is added to subpart B to read as follows:
Sec. 179.22 Marking.
In addition to any other marking requirement in this subchapter,
the following marking requirements apply:
(a) Each tank car must be marked according to the requirements in
Appendix C of the AAR Specifications for Tank Cars.
(b) Each tank car that is equipped with a tank-head puncture-
resistance system must have the letter ``S'' substituted for the letter
``A'' in the specification marking.
(c) Each tank car that is equipped with a tank-head puncture-
resistance system, a thermal protection system, and a metal jacket must
have the letter ``J'' substituted for the letter ``A'' or ``S'' in the
specification marking.
(d) Each tank car that is equipped with a tank-head puncture-
resistance system, a thermal protection system, and no metal jacket
must have the letter ``T'' substituted for the letter ``A'' or ``S'' in
the specification marking.
Sec. 179.100-4 [Amended]
20. In Sec. 179.100-4, in paragraph (a), the last sentence is
amended by removing the phrase ``except that a protective coating is
not required when foam-in-place insulation that adheres to the tank or
jacket is applied''.
Secs. 179.100-21 and 179.100-23 [Removed]
21. Sections 179.100-21 and 179.100-23 are removed.
22. In Sec. 179.101-1, in paragraph (a), Note 4 following the table
is revised to read as follows:
Sec. 179.101-1 Individual specification requirements.
(a) * * *
\4\ Tank cars not equipped with a thermal protection or an
insulation system used for the transportation of a Class 2
(compressed gas) material must have at least the upper two-thirds of
the exterior of the tank, including manway nozzle and all
appurtenances in contact with this area, finished with a reflective
coat of white paint.
* * * * *
Sec. 179.103-1 [Amended]
23. In Sec. 179.103-1, paragraph (c) is removed and reserved.
24. In Sec. 179.103-2, paragraph (a) is revised to read as follows:
Sec. 179.103-2 Manway cover.
(a) The manway cover must be an approved design.
* * * * *
Sec. 179.103-5 [Amended]
25. In Sec. 179.103-5, paragraph (a)(1) is amended by removing the
first two sentences.
Secs. 179.105, 179.105-1--179.105-8 [Removed]
26. Sections 179.105, 179.105-1 through 179.105-8 are removed.
27. In Sec. 179.200-4, in paragraph (a), the last sentence is
revised to read as follows:
[[Page 49078]]
Sec. 179.200-4 Insulation.
(a) * * * The exterior surface of a carbon steel tank and the
inside surface of a carbon steel jacket must be given a protection
coating.
* * * * *
Secs. 179.200-25 and 179.200-27 [Removed]
28. Sections 179.200-25 and 179.200-27 are removed.
Secs. 179.203, 179.203-1--179.203-3 [Removed]
29. Sections 179.203, 179.203-1 through 179.203-2 are removed.
30. Appendixes A and B are added to Part 179 to read as follows:
Appendix A to Part 179--Procedures for Tank-Head Puncture-Resistance
Test
1. This test procedure is designed to verify the integrity of
new or untried tank-head puncture-resistance systems and to test for
system survivability after coupler-to-tank-head impacts at relative
speeds of 29 km/hour (18 mph).
2. Tank-head puncture-resistance test. A tank-head puncture-
resistance system must be tested under the following conditions:
a. The ram car used must weigh at least 119,295 kg (263,000
pounds), be equipped with a coupler, and duplicate the condition of
a conventional draft sill including the draft yoke and draft gear.
The coupler must protrude from the end of the ram car so that it is
the leading location of perpendicular contact with the impacted test
car.
b. The impacted test car must be loaded with water at six
percent outage with internal pressure of at least 6.9 Bar (100 psi)
and coupled to one or more ``backup'' cars which have a total weight
of 217,724 kg (480,000 pounds) with hand brakes applied on the last
``backup'' car.
c. At least two separate tests must be conducted with the
coupler on the vertical centerline of the ram car. One test must be
conducted with the coupler at a height of 53.3 cm (21 inches), plus-
or-minus 2.5 cm (1 inch), above the top of the sill; the other test
must be conducted with the coupler height at 79 cm (31 inches),
plus-or-minus 2.5 cm (1 inch), above the top of the sill. If the
combined thickness of the tank head and any additional shielding
material is less than the combined thickness on the vertical
centerline of the car, a third test must be conducted with the
coupler positioned so as to strike the thinnest point of the tank
head.
3. One of the following test conditions must be applied:
------------------------------------------------------------------------
Minimum
Minimum weight of attached velocity of
ram cars in kg (pounds) impact in km/ Restrictions
hour (mph)
------------------------------------------------------------------------
119,295 (263,000)........... 29 (18)...... One ram car only.
155,582 (343,000)........... 25.5 (16).... One ram car or one car plus
one rigidly attached car.
311,164 (686,000)........... 22.5 (14).... One ram car plus one or
more rigidly attached
cars.
------------------------------------------------------------------------
4. A test is successful if there is no visible leak from the
standing tank car for at least one hour after impact.
Appendix B to Part 179--Procedures for Simulated Pool and Torch-Fire
Testing
1. This test procedure is designed to measure the thermal
effects of new or untried thermal protection systems and to test for
system survivability when exposed to a 100-minute pool fire and a
30-minute torch fire.
2. Simulated pool fire test.
a. A pool-fire environment must be simulated in the following
manner:
(1) The source of the simulated pool fire must be hydrocarbon
fuel with a flame temperature of 871 deg.C (1,600 deg.F), plus-or-
minus 37.8 deg.C (100 deg.F), throughout the duration of the test.
(2) A square bare plate with thermal properties equivalent to
the material of construction of the tank car must be used. The plate
dimensions must be not less than one foot by one foot by nominal 1.6
cm (0.625 inch) thick. The bare plate must be instrumented with not
less than nine thermocouples to record the thermal response of the
bare plate. The thermocouples must be attached to the surface not
exposed to the simulated pool fire and must be divided into nine
equal squares with a thermocouple placed in the center of each
square.
(3) The pool-fire simulator must be constructed in a manner that
results in total flame engulfment of the front surface of the bare
plate. The apex of the flame must be directed at the center of the
plate.
(4) The bare plate holder must be constructed in such a manner
that the only heat transfer to the back side of the bare plate is by
heat conduction through the plate and not by other heat paths.
(5) Before the bare plate is exposed to the simulated pool fire,
none of the temperature recording devices may indicate a plate
temperature in excess of 37.8 deg.C (100 deg.F) nor less than 0
deg.C (32 deg.F).
(6) A minimum of two thermocouple devices must indicate 427
deg.C (800 deg.F) after 13 minutes, plus-or-minus one minute, of
simulated pool-fire exposure.
b. A thermal protection system must be tested in the simulated
pool-fire environment described in paragraph 2a of this appendix in
the following manner:
(1) The thermal protection system must cover one side of a bare
plate as described in paragraph 2a(2) of this appendix.
(2) The non-protected side of the bare plate must be
instrumented with not less than nine thermocouples placed as
described in paragraph 2a(2) of this appendix to record the thermal
response of the plate.
(3) Before exposure to the pool-fire simulation, none of the
thermocouples on the thermal protection system configuration may
indicate a plate temperature in excess of 37.8 deg.C (100 deg.F)
nor less than 0 deg.C (32 deg.F).
(4) The entire surface of the thermal protection system must be
exposed to the simulated pool fire.
(5) A pool-fire simulation test must run for a minimum of 100
minutes. The thermal protection system must retard the heat flow to
the plate so that none of the thermocouples on the non-protected
side of the plate indicate a plate temperature in excess of 427
deg.C (800 deg.F).
(6) A minimum of three consecutive successful simulation fire
tests must be performed for each thermal protection system.
3. Simulated torch fire test.
a. A torch-fire environment must be simulated in the following
manner:
(1) The source of the simulated torch must be a hydrocarbon fuel
with a flame temperature of 1,204 deg.C (2,200 deg.F), plus-or-
minus 37.8 deg.C (100 deg.F), throughout the duration of the test.
Furthermore, torch velocities must be 64.4 km/h 16 km/h
(40 mph 10 mph) throughout the duration of the test.
(2) A square bare plate with thermal properties equivalent to
the material of construction of the tank car must be used. The plate
dimensions must be at least four feet by four feet by nominal 1.6 cm
(0.625 inch) thick. The bare plate must be instrumented with not
less than nine thermocouples to record the thermal response of the
plate. The thermocouples must be attached to the surface not exposed
to the simulated torch and must be divided into nine equal squares
with a thermocouple placed in the center of each square.
(3) The bare plate holder must be constructed in such a manner
that the only heat transfer to the back side of the plate is by heat
conduction through the plate and not by other heat paths. The apex
of the flame must be directed at the center of the plate.
(4) Before exposure to the simulated torch, none of the
temperature recording devices may indicate a plate temperature in
excess of 37.8 deg.C (100 deg.F) or less than 0 deg.C (32
deg.F).
(5) A minimum of two thermocouples must indicate 427 deg.C (800
deg.F) in four minutes, plus-or-minus 30 seconds, of torch
simulation exposure.
b. A thermal protection system must be tested in the simulated
torch-fire environment described in paragraph 3a of this appendix in
the following manner:
(1) The thermal protection system must cover one side of the
bare plate identical to that used to simulate a torch fire under
paragraph 3a(2) of this appendix.
(2) The back of the bare plate must be instrumented with not
less than nine thermocouples placed as described in
[[Page 49079]]
paragraph 3a(2) of this appendix to record the thermal response of the
material.
(3) Before exposure to the simulated torch, none of the
thermocouples on the back side of the thermal protection system
configuration may indicate a plate temperature in excess of 37.8
deg.C (100 deg.F) nor less than 0 deg.C (32 deg.F).
(4) The entire outside surface of the thermal protection system
must be exposed to the simulated torch-fire environment.
(5) A torch-simulation test must be run for a minimum of 30
minutes. The thermal protection system must retard the heat flow to
the plate so that none of the thermocouples on the backside of the
bare plate indicate a plate temperature in excess of 427 deg.C (800
deg.F).
(6) A minimum of two consecutive successful torch-simulation
tests must be performed for each thermal protection system.
PART 180--CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS
31. The authority citation for part 180 continues to read as
follows:
Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.
32. A new Subpart F is added to part 180 to read as follows:
Subpart F--Qualification and Maintenance of Tank Cars
Sec.
180.501 Applicability.
180.503 Definitions.
180.505 Quality assurance program.
180.507 Qualification of tank cars.
180.509 Requirements for inspection and test of specification tank
cars.
180.511 Acceptable results of inspections and tests.
180.513 Repairs, alterations, conversions, and modifications.
180.515 Markings.
180.517 Reporting and record retention requirements.
180.519 Periodic retest and inspection of tank cars other than
single-unit tank car tanks.
Subpart F--Qualification and Maintenance of Tank Cars
Sec. 180.501 Applicability.
(a) This subpart prescribes requirements, in addition to those
contained in parts 107, 171, 172, 173, and 179 of this subchapter,
applicable to any person who manufactures, fabricates, marks,
maintains, repairs, inspects, or services tank cars to ensure that the
tank cars are in proper condition for transportation.
(b) Any person who performs a function prescribed in this part
shall perform that function in accordance with this part.
Sec. 180.503 Definitions.
The definitions contained in Secs. 171.8 and 179.2 of this
subchapter apply.
Sec. 180.505 Quality assurance program.
The quality assurance program requirements of Sec. 179.7 of this
subchapter apply.
Sec. 180.507 Qualification of tank cars.
(a) Each tank car marked as meeting a ``DOT'' specification or any
other tank car used for the transportation of a hazardous material must
meet the requirements of this subchapter or the applicable
specification to which the tank was constructed.
(b) Tank car specifications no longer authorized for construction.
(1) Tank cars prescribed in the following table are authorized for
service provided they conform to all applicable safety requirements of
this subchapter:
------------------------------------------------------------------------
Specification prescribed in the
current regulations Other specifications permitted Notes
------------------------------------------------------------------------
105A200W....................... 105A100W....................... 1
105A200ALW..................... 105A100ALW..................... 1
105A300W....................... ICC-105, 105A300...............
105A400W....................... 105A400........................
105A500W....................... 105A500........................
105A600W....................... 105A600........................
106A500X....................... ICC-27, BE-27, 106A500.........
106A800X....................... 106A800........................
107A * * * *................... ............................... 2
------------------------------------------------------------------------
Note 1: Tanks built as Specification DOT 105A100W or DOT 105A100ALW may
be altered and converted to DOT 105A200W and DOT 105A200ALW,
respectively.
Note 2: The test pressures of tanks built in the United States between
January 1, 1941 and December 31, 1955, may be increased to conform to
Specification 107A. Original and revised test pressure markings must
be indicated and may be shown on the tank or on a plate attached to
the bulkhead of the car. Tanks built before 1941 are not authorized.
(2) For each tank car conforming to and used under an exemption
issued before October 1, 1984, which authorized the transportation of a
cryogenic liquid in a tank car, the owner or operator shall remove the
exemption number stenciled on the tank car and stamp the tank car with
the appropriate Class DOT-113 specification followed by the applicable
exemption number. For example: DOT-113D60W-E * * * * (asterisks to be
replaced by the exemption number). The owner or operator marking a tank
car in this manner shall retain on file a copy of the last exemption in
effect during the period the tank car is in service. No person may
modify a tank car marked under this paragraph unless the modification
is in compliance with an applicable requirement or provision of this
subchapter.
(3) Specification DOT-113A175W, DOT-113C60W, DOT-113D60W, and DOT-
113D120W tank cars may continue in use, but new construction is not
authorized.
(4) Class DOT 105A and 105S tank cars used to transport hydrogen
chloride, refrigerated liquid under the terms of DOT-E 3992 may
continue in service, but new construction is not authorized.
Sec. 180.509 Requirements for inspection and test of specification
tank cars.
(a) General. (1) Each tank car facility shall evaluate a tank car
according to the requirements specified in Sec. 180.511.
(2) Each tank car that successfully passes a periodic inspection
and test must be marked as prescribed in Sec. 180.515.
(3) A written report as specified in Sec. 180.517(b) must be
prepared for each tank car that is inspected and tested under this
section.
(b) Conditions requiring inspection and test of tank cars. Without
regard to any other periodic inspection and test requirement, a tank
car must have an inspection and test according to this section if:
(1) The tank car shows evidence of abrasion, corrosion, cracks,
dents, distortions, defects in welds, or any other condition that makes
the tank car unsafe for transportation.
(2) The tank car was in an accident and damaged to an extent that
may adversely affect its capability to retain its contents.
(3) The tank bears evidence of damage caused by fire.
(4) The Associate Administrator for Safety, FRA, requires it based
on the existence of probable cause that a tank car or a class or design
of tank cars may be in an unsafe operating condition.
(c) Frequency of inspection and tests. Each tank car shall have an
inspection and test according to the requirements of this paragraph.
(1) For Class 107 tank cars and tank cars of riveted construction,
the tank car must have a hydrostatic pressure test and visual
inspection conforming to the requirements in effect prior to July 1,
1996, for the tank specification.
(2) For Class DOT 113 tank cars, see Sec. 173.319(e) of this
subchapter.
(3) For fusion welded tank cars, each tank car must have an
inspection and test in accordance with paragraphs (d) through (k) of
this section.
(i) For cars transporting materials not corrosive to the tank,
every 10 years for the tank and service equipment (i.e., filling and
discharge, venting, safety, heating, and measuring devices).
(ii) For non-lined or non-coated tank cars transporting materials
corrosive to the tank, an interval based on the following formula, but
in no case shall
[[Page 49080]]
the interval exceed 10 years for the tank and 5 years for service
equipment:
t1-t2
i = ----------
r
where:
i is the inspection and test interval.
t1 is the actual thickness.
t2 is the allowable minimum thickness under paragraph (g) of this
section.
r is the corrosion rate per year.
(iii) For lined or coated tank cars transporting a material
corrosive to the tank, every 10 years for the tank, 5 years for the
service equipment, and when a lining or coating is applied to protect
the tank shell from the lading, an interval based on the owner's
determination for the lining or coating, but not greater than every 10
years.
(A) When a lining or coating is applied to protect the tank shell
from the lading, each owner of a lining or coating shall determine the
periodic inspection interval and test technique for the lining or
coating. The owner must maintain all supporting documentation used to
make such a determination, such as the lining or coating manufacturer's
recommended inspection interval and test technique, at the owner's
principal place of business.
(B) The supporting documentation used to make such inspection and
test interval determinations and technique must be made available to
FRA upon request.
(d) Visual inspection. At a minimum, each tank car facility must
visually inspect the tank externally and internally as follows:
(1) An internal inspection of the tank shell and heads for
abrasion, corrosion, cracks, dents, distortions, defects in welds, or
any other condition that makes the tank car unsafe for transportation,
and except in the areas where insulation or a thermal protection system
precludes it, an external inspection of the tank shell and heads for
abrasion, corrosion, cracks, dents, distortions, defects in welds, or
any other condition that makes the tank car unsafe for transportation;
(2) An inspection of the piping, valves, fittings, and gaskets for
indications of corrosion and other conditions that make the tank car
unsafe for transportation;
(3) An inspection for missing or loose bolts, nuts, or elements
that make the tank car unsafe for transportation;
(4) An inspection of all closures on the tank car for proper
securement in a tool tight condition and an inspection of the
protective housings for proper securement;
(5) An inspection of excess flow valves having threaded seats for
tightness; and
(6) An inspection of the required markings on the tank car for
legibility.
(e) Structural integrity inspections and tests. At a minimum, each
tank car facility shall inspect the tank car for structural integrity
as specified in this section. The structural integrity inspection and
test shall include all transverse fillet welds greater than 0.64 cm
(0.25 inch) within 121.92 cm (4 feet) of the bottom longitudinal center
line; the termination of longitudinal fillet welds greater than 0.64 cm
(0.25 inch) within 121.92 cm (4 feet) of the bottom longitudinal center
line; and all tank shell butt welds within 60.96 cm (2 feet) of the
bottom longitudinal center line by one or more of the following
inspection and test methods to determine that the welds are in proper
condition:
(1) Dye penetrant test;
(2) Radiography test;
(3) Magnetic particle test;
(4) Ultrasonic test; or
(5) Optically-aided visual inspection (e.g., magnifiers,
fiberscopes, borescopes, and machine vision technology).
(f) Thickness tests. (1) Each tank car facility shall measure the
thickness of the tank car shell, heads, sumps, domes, and nozzles on
each tank car by using a device capable of accurately measuring the
thickness to within 0.05 mm (0.002 inch).
(2) After repairs, alterations, conversions or modifications of a
tank car that result in a reduction to the tank car shell thickness,
the tank car facility shall measure the thickness of the tank car shell
in the area of reduced shell thickness to ensure that the shell
thickness conforms to paragraph (g) of this section.
(g) Service life shell thickness allowance. (1) A tank car found
with a shell thickness below the required minimum thickness after
forming for its specification, as stated in part 179 of this
subchapter, may continue in service if:
(i) Construction of the tank car shell and heads is from carbon
steel, stainless steel, aluminum, nickel, or manganese-molybdenum
steel; and
(ii) Any reduction in thickness of the tank shell or head is not
more than that provided in the following table:
Allowable Shell Thickness Reductions
----------------------------------------------------------------------------------------------------------------
Class DOT 103, 104, 111, and 115 tank Class DOT 105, 109, 112, and 114 tank cars
cars -----------------------------------------------------
Damage type ----------------------------------------
Top shell Bottom shell Top shell Bottom shell
----------------------------------------------------------------------------------------------------------------
Corrosion......... 3.17 mm (0.125 1.58 mm (0.063 0.79 mm (0.031 0.79 mm (0.031 inch).
inch). inch). inch).
Corrosion and 3.17 mm (0.125 1.58 mm (0.063 0.79 mm (0.031 0.79 mm (0.031 inch).
mechanical. inch). inch). inch).
Corrosion, local.. 4.76 mm (\3/16\ 3.17 mm (0.125 1.58 mm (0.063 1.58 mm (0.063 inch).
inch). inch). inch).
Mechanical, local. 3.17 mm (0.125 1.58 mm (0.063 1.58 mm (0.063 1.58 mm (0.063 inch).
inch). inch). inch).
Corrosion and 4.76 mm (\3/16\ 3.17 mm (0.125 1.58 mm (0.063 1.58 mm (0.063 inch).
mechanical, local. inch). inch). inch).
----------------------------------------------------------------------------------------------------------------
Notes:
1. The perimeter for a local reduction may not exceed a 60.96 cm (24 inch) perimeter. Local reductions in the
top shell must be separated from other reductions in the top shell by at least 40.64 cm (16 inches). The
cumulative perimeter for local reductions in the bottom shell may not exceed 182.88 cm (72 inches).
2. Any reduction in the tank car shell may not affect the structural strength of the tank car so that the tank
car shell no longer conforms to Section 6.2 of the AAR Specifications for Tank Cars.
3. Any reduction applies only to the outer shell for Class DOT 115 tank cars.
4. For Class DOT 103 and 104 tank cars, the inside diameter may not exceed 243.84 cm (96 inches).
(h) Safety system inspections. At a minimum, each tank car
facility must inspect:
(1) Tank car thermal protection systems, tank head puncture
resistance systems, coupler vertical restraint systems, and systems
used to protect discontinuities (i.e., skid protection and protective
housings) to ensure their integrity.
[[Page 49081]]
(2) Reclosing pressure relief devices by:
(i) Removing the safety relief device from the tank car for
inspection; and
(ii) Testing the safety relief device with air or another gas to
ensure that it conforms to the start-to-discharge pressure for the
specification or hazardous material in this subchapter.
(i) Lining and coating inspection and test. When this subchapter
requires a lining or coating, at a minimum, each tank car facility must
inspect the lining or coating installed on the tank car according to
the inspection interval and test technique established by the owner of
the lining or coating in accordance with paragraph (c)(3)(iii) of this
section.
(j) Leakage pressure test. (1) At a minimum, each tank car facility
shall perform a leakage pressure test on the tank fittings and
appurtenances. The leakage pressure test must include product piping
with all valves and accessories in place and operative, except that
during the pressure test the tank car facility shall remove or render
inoperative any venting devices set to discharge at less than the test
pressure. Test pressure must be maintained for at least 5 minutes.
Leakage test pressure may not be less than 2.1 Bar (30 psig) for tank
cars having a test pressure less than or equal to 13.8 Bar (200 psig),
or 3.4 Bar (50 psig) for tank cars having a tank test pressure greater
than 13.8 Bar (200 psig).
(2) Interior heater systems must be tested hydrostatically at 13.87
Bar (200 psi) and must show no signs of leakage.
(k) Alternative inspection and test procedures. In lieu of the
other requirements of this section, a person may use an alternative
inspection and test procedure or interval based on a damage-tolerance
fatigue evaluation (that includes a determination of the probable
locations and modes of damage due to fatigue, corrosion, or accidental
damage), when the evaluation is examined by the Association of American
Railroads Tank Car Committee and approved by the Associate
Administrator for Safety, FRA.
(l) Inspection and test compliance date for tank cars with metal
jackets or thermal protection systems. (1) After July 1, 2000, each
tank car with a metal jacket or with a thermal protection system shall
have an inspection and test conforming to this section no later than
the date the tank car requires a periodic hydrostatic pressure test
(i.e., the marked due date on the tank car for the hydrostatic test).
(2) After July 1, 1998, each tank car without a metal jacket shall
have an inspection and test conforming to this section no later than
the date the tank car requires a periodic hydrostatic pressure test
(i.e., the marked due date on the tank car for the hydrostatic test).
(3) For tank cars on a 20-year periodic hydrostatic pressure test
interval (i.e., Class DOT 103W, 104W, 111A60W1, 111A100W1, and
111A100W3 tank cars), the next inspection and test date is the midpoint
between the compliance date in paragraph (l)(1) or (2) of this section
and the remaining years until the tank would have had a hydrostatic
pressure test.
Sec. 180.511 Acceptable results of inspections and tests.
Provided it conforms with other applicable requirements of this
subchapter, a tank car is qualified for use if it successfully passes
the following inspections and tests conducted in accordance with this
subpart:
(a) Visual inspection. A tank car successfully passes the visual
inspection when the inspection shows no structural defect that may
cause leakage from or failure of the tank before the next inspection
and test interval.
(b) Structural integrity inspection and test. A tank car
successfully passes the structural integrity inspection and test when
it shows no structural defect that may initiate cracks or propagate
cracks and cause failure of the tank before the next inspection and
test interval.
(c) Service life shell thickness. A tank car successfully passes
the service life shell thickness inspection when the tank shell and
heads show no thickness reduction below that allowed in
Sec. 180.509(g).
(d) Safety system inspection. A tank car successfully passes the
safety system inspection when each thermal protection system, tank head
puncture resistance system, coupler vertical restraint system, and
system used to protect discontinuities (e.g., breakage grooves on
bottom outlets and protective housings) on the tank car conform to this
subchapter.
(e) Lining and coating inspection. A tank car successfully passes
the lining and coating inspection and test when the lining or coating
shows no evidence of holes or degraded areas.
(f) Leakage pressure test. A tank car successfully passes the
leakage pressure test when all product piping, fittings and closures
show no indication of leakage.
(g) Hydrostatic test. A Class 107 tank car or a riveted tank car
successfully passes the hydrostatic test when it shows no leakage,
distortion, excessive permanent expansion, or other evidence of
weakness that might render the tank car unsafe for transportation
service.
Sec. 180.513 Repairs, alterations, conversions, and modifications.
(a) In order to repair tank cars, the tank car facility must comply
with the requirements of Appendix R of the AAR Specifications for Tank
Cars.
(b) Unless the exterior tank car shell or interior tank car jacket
has a protective coating, after a repair that requires the complete
removal of the tank car jacket, the exterior tank car shell and the
interior tank car jacket must have a protective coating applied to
prevent the deterioration of the tank shell and tank jacket.
Sec. 180.515 Markings.
(a) When a tank car passes the required inspection and test with
acceptable results, the tank car facility shall mark the date of the
inspection and test and the due date of the next inspection and test on
the tank car in accordance with paragraph (b) of this section. When a
tank car facility performs multiple inspection and test at the same
time, one date may be used to satisfy the requirements of this section.
One date also may be shown when multiple inspection and test have the
same due date.
(b) The tank car facility must comply with the marking requirements
of Appendix C of the AAR Specifications for Tank Cars.
(c) Converted tank cars must have the new specification and
conversion date permanently marked in letters and figures at least 0.95
cm (0.375 inch) high on the outside of the manway nozzle or the edge of
the manway nozzle flange on the left side of the car. The marking may
have the last numeral of the specification number omitted (e.g., ``DOT
111A100W'' instead of ``DOT 111A100W1'').
(d) When pressure tested within six months of installation and
protected from deterioration, the test date marking of a safety relief
device is the installation date on the tank car.
Sec. 180.517 Reporting and record retention requirements.
(a) Certification and representation. Each owner of a specification
tank car shall retain the certificate of construction (AAR Form 4-2)
and related papers certifying that the manufacture of the specification
tank car identified in the documents is in accordance with the
applicable specification. The owner shall retain the documents
throughout the period of ownership of the specification tank car and
for one year thereafter. Upon a
[[Page 49082]]
change of ownership, the requirements of Section 1.3.15 of the AAR
Specifications for Tank Cars apply.
(b) Inspection and test reporting. Each tank car that is inspected
as specified in Sec. 180.509 must have a written report, in English,
prepared according to this paragraph. The owner must retain a copy of
the inspection and test reports until successfully completing the next
inspection and test of the same type. The inspection and test report
must include the following:
(1) Type of inspection and test performed (a checklist is
acceptable);
(2) The results of each inspection and test performed;
(3) Owner's reporting mark;
(4) DOT Specification;
(5) Inspection and test date (month and year);
(6) Location and description of defects found and method used to
repair each defect;
(7) The name and address of the tank car facility and the signature
of inspector.
Sec. 180.519 Periodic retest and inspection of tank cars other than
single-unit tank car tanks.
(a) General. Unless otherwise provided in this subpart, tanks
designed to be removed from cars for filling and emptying and tanks
built to a Class DOT 107A specification and their safety relief devices
must be retested periodically as specified in Retest Table 1 of
paragraph (b)(5) of this section. Retests may be made at any time
during the calendar year the retest falls due.
(b) Pressure test. (1) Each tank, except as provided in paragraph
(b)(8) of this section, must be subjected to the specified hydrostatic
pressure and its permanent expansion determined. Pressure must be
maintained for 30 seconds and far as long as necessary to secure
complete expansion of the tank. Before testing, the pressure gauge must
be shown to be accurate within 1 percent at test measure. The expansion
gauge must be shown to be accurate, at test pressure, to within 1
percent. Expansion must be recorded in cubic centimeters. Permanent
volumetric expansion may not exceed 10 percent of total volumetric
expansion at test pressure and the tank must not leak or show evidence
of distress.
(2) Each tank, except tanks built to specification DOT 107A, must
also be subjected to interior air pressure test of at least 100 psi
under conditions favorable to detection of any leakage. No leaks may
appear.
(3) Safety relief valves must be retested by air or gas, must start
to discharge at or below the prescribed pressure and must be vapor
tight at or above the prescribed pressure.
(4) Frangible discs and fusible plugs must be removed from the tank
and visually inspected.
(5) Tanks must be retested as specified in Retest Table 1 of this
paragraph (b)(5), and before returning to service after repairs
involving welding or heat treatment:
Retest Table 1
----------------------------------------------------------------------------------------------------------------
Retest interval--years Minimum Retest pressure-- Safety relief valve
-------------------------- p.s.i. pressure--p.s.i.
---------------------------------------------------
Specification Safety Tank
Tank relief hydrostatic Tank air Start-to- Vapor tight
devicesd expansionc test discharge
----------------------------------------------------------------------------------------------------------------
DOT 27............................ 5 2 500 100 375 300
106A500........................... 5 2 500 100 375 300
106A500X.......................... 5 2 500 100 375 300
106A800........................... 5 2 800 100 600 480
106A800X.......................... 5 2 800 100 600 480
106A800NCI........................ 5 2 800 100 600 480
107A * * * *...................... d5 a2 (b) None None None
110A500-W......................... 5 2 500 100 375 300
110A600-W......................... 5 2 600 100 500 360
110A800-W......................... 5 2 800 100 600 480
110A1000-W........................ 5 2 1,000 100 750 600
BE-275............................ 5 2 500 100 375 300
----------------------------------------------------------------------------------------------------------------
Notes:
aIf DOT 107A * * * * tanks are used for transportation of flammable gases, one frangible disc from each car must
be burst at the interval prescribed. The sample disc must burst at a pressure not exceeding the marked test
pressure of the tank and not less than 70 percent of the marked test pressure. If the sample disc does not
burst within the prescribed limits, all discs on the car must be replaced.
bThe hydrostatic expansion test pressure must at least equal the marked test pressure.
cSee Sec. 180.519(b)(1).
dSafety relief valves of the spring-loaded type on tanks used exclusively for fluorinated hydrocarbons and
mixtures thereof which are free from corroding components may be retested every 5 years.
(6) The month and year of test, followed by a ``V'' if visually
inspected as described in paragraph (d)(8) of this section, must be
plainly and permanently stamped into the metal of one head or chime of
each tank with successful test results; for example, 1-60 for January
1960. On DOT 107A**** tanks, the date must be stamped into the metal of
the marked end, except that if all tanks mounted on a car have been
tested, the date may be stamped into the metal of a plate permanently
applied to the bulkhead on the ``A'' end of the car. Dates of previous
tests and all prescribed markings must be kept legible.
(c) Visual inspection. Tanks of Class DOT 106A and DOT 110A-Z
specifications (Secs. 179.300, 179.301, 179.302 of this subchapter)
used exclusively for transporting fluorinated hydrocarbons and mixtures
thereof, and that are free from corroding components, may be given a
periodic complete internal and external visual inspection in place of
the periodic hydrostatic retest. Visual inspections shall be made only
by competent persons. The tank must be accepted or rejected in
accordance with the criteria in CGA Pamphlet C-6.
(d) Written records. The results of the pressure test and visual
inspection must be recorded on a suitable data sheet. Completed copies
of these reports must be retained by the owner and by the person
performing the pressure test and visual inspection as long as the tank
is in service. The information to be recorded and checked on these data
[[Page 49083]]
sheets are: Date of test and inspection; DOT specification number; tank
identification (registered symbol and serial number, date of
manufacture and ownership symbol); type of protective coating (painted,
etc., and statement as to need for refinishing or recoating);
conditions checked (leakage, corrosion, gouges, dents or digs, broken
or damaged chime or protective ring, fire, fire damage, internal
condition); test pressure; results of tests; and disposition of tank
(returned to service, returned to manufacturer for repair, or
scrapped); and identification of the person conducting the retest or
inspection.
Issued in Washington, DC, on September 7, 1995 under authority
delegated in 49 CFR Part 1.
D.K. Sharma,
Administrator.
[FR Doc. 95-22771 Filed 9-20-95; 8:45 am]
BILLING CODE 4910-60-P
