[Federal Register Volume 62, Number 166 (Wednesday, August 27, 1997)]
[Proposed Rules]
[Pages 45369-45377]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-22508]
[[Page 45369]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 60, 61, and 63
[FRL-5880-8]
RIN 2060-AG21
Amendments for Testing and Monitoring Provisions
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule: Amendments.
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SUMMARY: This action proposes amendments to 40 CFR parts 60, 61, and 63
to reflect miscellaneous editorial changes and technical corrections
throughout the parts in sections pertaining to source testing or
monitoring of emissions and operations, and proposes to add Performance
Specification 15 (PS 15) to Appendix B of Part 60. In addition, the
test methods in Appendix A of Part 60, Appendix B of Part 61, Appendix
A of Part 63, and the performance specifications in Appendix B of Part
60 are proposed to be restructured in the format recommended by the
Environmental Monitoring Management Council (EMMC) to achieve
uniformity and consistency between Agency methods. The editorial
changes and technical corrections to the subparts, test methods, and/or
performance specifications in Parts 60, 61, and 63 are proposed to
maintain the intent of the regulations.
DATES: Comments. Comments must be received on or before October 27,
1997 unless a hearing is requested by September 8, 1997. If a hearing
is requested, written comments must be received by October 14, 1997.
Public Hearing. Anyone requesting a public hearing must contact EPA
no later than September 8, 1997. If a hearing is held, it will take
place on September 10, 1997, beginning at 9:00 a.m.
Request To Speak at Hearing. Persons wishing to present oral
testimony must contact EPA by September 10, 1997.
ADDRESSES: Comments. Comments should be submitted (in duplicate, if
possible) to: Air and Radiation Docket and Information Center (6102),
Attention Docket No. A-97-12 (see docket section below), room M-1500,
U.S. Environmental Protection Agency, 401 M Street, SW., Washington, DC
20460. The Agency requests that a separate copy also be sent to the
person listed in the FOR FURTHER INFORMATION CONTACT section below.
Public Hearing. If anyone contacts EPA requesting a public hearing,
it will be held at the EPA's Emissions Measurement Laboratory, Research
Triangle Park, North Carolina. Persons interested in attending the
hearing or wishing to present oral testimony should notify Ms. Lala
Cheek (MD-19), U.S. Environmental Protection Agency, Research Triangle
Park, NC 27711, telephone (919) 541-5545.
Docket. Docket No. A-97-12, containing materials relevant to this
rulemaking, is available for public inspection and copying between 8:00
a.m. and 5:30 p.m., Monday through Friday, except for Federal holidays,
at the EPA's Air and Radiation Docket and Information Center, Room M-
1500, U.S. Environmental Protection Agency, 401 M Street, SW.,
Washington, DC 20460; telephone (202) 260-7548. A reasonable fee may be
charged for copying.
FOR FURTHER INFORMATION CONTACT:
Mr. Foston Curtis, Emission Measurement Center (MD-19), Emissions,
Monitoring, and Analysis Division, U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina 27711, telephone number
(919) 541-1063 or at fax number (919) 541-1039.
SUPPLEMENTARY INFORMATION: The information presented in this preamble
is organized as follows:
I. Background and Purpose
II. EMMC Format
III. Significant Technical Revisions to Specific Test Methods,
Performance Specifications, and Rules
A. General
B. ASTM Methods Updates
C. Continuous Instrumental Methods (Part 60, Appendix A)--
Methods 3A, 6C, 7E, 10, and 20
D. Method 5 (Part 60, Appendix A)
E. Method 5E (Part 60, Appendix A)
F. Method 5H (Part 60, Appendix A)
G. Method 18 (Part 60, Appendix A)
H. Methods 306, 306A, and 306B (Part 63, Appendix A)
IV. Addition of Performance Specification 15
V. Copies of Regulatory Text
VI. Administrative Requirements
A. Docket
B. Office of Management and Budget Review
C. Regulatory Flexibility Act
D. Paperwork Reduction Act
E. Unfunded Mandates Reform Act
I. Background and Purpose
As part of its efforts to promote methods consolidation and
integration between EPA Program Offices, the EMMC developed a consensus
format for documentation of analytical methods. The Office of Air and
Radiation has adapted the format for its new methods and is attempting
to update its existing methods to this format. The EMMC format is shown
in Section II. To achieve consistency between the test methods and
performance specifications, EPA is proposing to restructure the test
methods and performance specifications shown in Table 1 in the EMMC
format. In addition, EPA reviewed the test methods and performance
specifications and associated regulations in 40 CFR Parts 60, 61, and
63 and found that corrections and revisions were necessary. The
corrections and revisions consisted primarily of typographical errors,
technical errors in equations and diagrams, and narrative that is no
longer applicable due to more recent additions. However, a few methods
required further revision due to needed technical updates and comments
received from the public. These methods are discussed in Section III.
It is important to note that although numerous technical corrections
were made to portions of the subparts in Parts 60, 61, and 63, changes
were not made to any compliance standard, reporting, or recordkeeping
requirement. For this notice, EPA is only proposing revisions to
sections of the subpart pertaining to source testing or monitoring of
emissions and operations.
II. EMMC Format
The test methods and performance specifications listed in Table 1
are being proposed in the restructured format shown in Table 2 which is
recommended by EMMC. Only in a few instances were there any deviations
from this recommended format.
Table 1.--Test Methods and Performance Specifications Restructured in the EMMC Format
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40 CFR 63, appendix
40 CFR part 60, appendix A 40 CFR part 60, appendix B 40 CFR 61, appendix B A
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1, 1a.......................... PS-2........................ 101, 101a................... 303, 303a
2, 2a, 2b, 2c,................. PS-3........................ 102......................... 304a,
2d, 2e......................... PS-4, PS-4a................. 103......................... 304b
3, 3a, 3b...................... PS-5........................ 104......................... 305
[[Page 45370]]
4.............................. PS-6........................ 105......................... 306,
5, 5a, 5b, 5d,................. PS-7........................ 106......................... 306a,
5e, 5f, 5g, 5h................. PS-8........................ 107, 107a................... 306b
6, 6a, 6b, 6c.................. PS-9........................ 108......................... ...................
7, 7a, 7b, 7c,................. ............................ 108a........................ ...................
7d, 7e......................... ............................ 108b........................ ...................
8.............................. ............................ 108c........................ ...................
10, 10a, 10b................... ............................ 111......................... ...................
11............................. ............................ ............................ ...................
12............................. ............................ ............................ ...................
13a, 13b....................... ............................ ............................ ...................
14............................. ............................ ............................ ...................
15, 15a........................ ............................ ............................ ...................
16, 16a, 16b................... ............................ ............................ ...................
17............................. ............................ ............................ ...................
18............................. ............................ ............................ ...................
19............................. ............................ ............................ ...................
20............................. ............................ ............................ ...................
21............................. ............................ ............................ ...................
22............................. ............................ ............................ ...................
23............................. ............................ ............................ ...................
24, 24a........................ ............................ ............................ ...................
25, 25a, 25b,.................. ............................ ............................ ...................
25c, 25d, 25e.................. ............................ ............................ ...................
26, 26a........................ ............................ ............................ ...................
27............................. ............................ ............................ ...................
28, 28a........................ ............................ ............................ ...................
29............................. ............................ ............................ ...................
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Table 2.--EMMC Format
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Section No. Section heading
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1.0................................. Scope and Application.
2.0................................. Summary of the Method.
3.0................................. Definitions.
4.0................................. Interferences.
5.0................................. Safety.
6.0................................. Equipment and Supplies.
7.0................................. Reagents and Standards.
8.0................................. Sample Collection, Preservation,
Storage and Transport.
9.0................................. Quality Control.
10.0................................ Calibration and Standardization.
11.0................................ Analytical Procedure.
12.0................................ Calculations and Data Analysis.
13.0................................ Method Performance.
14.0................................ Pollution Prevention.
15.0................................ Waste Management.
16.0................................ References.
17.0................................ Tables, Diagrams, Flowcharts, and
Validation Data.
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III. Significant Technical Revisions to Specific Test Methods,
Performance Specifications, and Rules
A. General
A safety section (Section 5) was added to most of the test methods
and performance specifications. This section discusses only those
safety issues specific to the method and any target analytes or
reagents that pose specific toxicity or safety issues.
B. ASTM Methods Updates
The American Society for Testing and Materials assisted EPA in
revising test method references of ASTM methods by providing an update
of all ASTM procedures cited in the test methods. Many Agency methods
cite obsolete versions of ASTM methods that have been improved and
redated or redesignated since the EPA methods were promulgated. Where
appropriate, the redated and redesignated versions are included to add
flexibility and clarify which methods may be used. In addition, the
Incorporation by Reference citations in Sec. 60.17 are amended to add
the updated ASTM versions. The Agency is grateful for ASTM's assistance
in this effort.
C. Continuous Instrumental Methods (Part 60, Appendix A)--Methods 3A,
6C, 7E, 10, and 20
The continuous instrumental methods have been coordinated to
require the same performance specifications and, where applicable, the
same testing procedures and equipment specifications.
D. Method 5 (Part 60, Appendix A)
Section 6.1.1.7 (formerly Section 2.1.6) specifies that a
temperature sensor be installed so that the sensing tip of the
temperature sensor is in direct contact with the sample gas and that
the temperature around the filter holder be regulated and monitored
during sampling. EPA recognized that, depending on the sampling
apparatus, temperature in the heating area may be measured at different
locations (e.g., near the heater or at the top of the heated area)
resulting in deviations from the recommended temperature range of
24825 deg.F. This modification was made so that temperature
inside the heating area is measured at a consistent location in the gas
stream. This modification requires that an extra temperature sensor be
used with the filter heating system.
E. Method 5E (Part 60, Appendix A)
Section 6.3.4 (formerly Section 2.3.4) no longer specifies the
Beckman Model 915 analyzer with a 215 B infrared or equivalent. Since
the Beckman Model 915 is no longer manufactured, the EPA determined
that the Rosemount Model 2100A TOC analyzer was comparable to the
Beckman 915 model. As a result, Section 6.3.4 no longer specifies the
Beckman Model 915 with 215 B infrared or equivalent but instead, the
Rosemount Model 2100A TOC analyzer.
F. Method 5H (Part 60, Appendix A)
Section 7.3.4.1 (formerly Section 3.3.1.4) has been revised to
specify that only three calibration gas levels (high-range, mid-range,
and zero gases) are needed to calibrate the carbon dioxide, carbon
monoxide, and sulfur dioxide
[[Page 45371]]
(SO2) analyzers instead of four calibration gas levels. The
low-range calibration gas is no longer required. This revision is
consistent with the gas levels used to calibrate the SO2
analyzer as described in Section 7.4 (formerly Section 5.3) of Method
6C (Determination of Sulfur Dioxide Emissions from Stationary Sources).
G. Method 18 (Part 60, Appendix A)
The Agency is soliciting comments on procedural modifications to
Method 18 being proposed in this action. In the direct interface
sampling procedure, the requirement for two consecutive samples to have
less than 5 percent difference is being replaced with taking 5
consecutive samples per run. This modification allows for direct
interface sampling to be used in cases where the process is highly
variable. The adsorbent tube procedure is being modified to allow the
source to choose any commercially available adsorbent material, instead
of relying on the few adsorbents listed in the previous version of the
method. In preparing calibration gases, it is proposed to allow the use
of gas dilution instruments meeting the requirements of Method 205 of
40 CFR part 51, appendix M.
H. Methods 306, 306A, and 306B (Part 63, Appendix A)
Numerous editorial revisions were made to clarify the requirements
of Methods 306, 306A, and 306B. The applicability sections of Methods
306, 306A, and 306B have been revised to add continuous chromium
plating at iron and steel facilities to the list of source categories
to which these methods apply. The requirement for filtration of all
samples to be analyzed by ion chromatography has been eliminated from
Section 9.2 (formerly Section 5.2.3) of Method 306 and Section 9.2
(formerly Section 5.2.3) of Method 306A. Instead, a qualifying note has
been added stating that filtration is not required if a sample does not
contain particulate matter. The filtration procedure would only apply
when visible particulate is present in the sample (chromium
electroplating and anodizing baths emit little, if any particulate);
when needed, the tester is referred to the filtration procedure in
Method 0061 in Test Methods for Evaluating Solid Waste, Physical/
Chemical Methods, SW-846 Manual, November 1986. Section 9.2.2 (formerly
Section 5.1) of Method 306 has been revised to modify the post-sampling
pH requirement for the sodium bicarbonate absorbing solution when it
will be submitted to analysis by ion chromatography for hexavalent
chromium. The pH must be 8.0 rather than 8.5, as
the sodium bicarbonate solution does not reach a pH of 8.5. This
requirement has also been added to Section 9.2.2 of Method 306A.
Specific requirements for sample storage and sample holding times have
been added to Sections 9.3 and 9.4, respectively, of Methods 306 and
306A. Section 9.1.2.3 (formerly Section 5.1.2.3) of Method 306A has
been revised to add an option to adjust the sample volume for leaks
discovered during the post-test leak-check. This option is consistent
with that of Method 5 (40 CFR part 60, appendix A).
IV. Addition of Performance Specification 15
Performance Specification 15 is being proposed for addition to
Appendix B of Part 60. Performance specification 15 may be used by
sources to certify extractive Fourier Transform Infrared spectroscopy
(FTIR) continuous emission monitors for regulated pollutants. The
specification will determine the acceptability of FTIR continuous
emission monitoring systems and is not source-specific. The procedure
gives the source the option of using several techniques for FTIR
certification including relative accuracy testing, spiking of target
compounds, and comparison of dual instruments.
V. Copies of Regulatory Text
The text of the other proposed amendments is not included in this
Federal Register action because of the magnitude of the reformatted
test methods and amendments. The significant proposed amendments are
discussed fully in this preamble. Performance Specification 15, which
is a new procedure, is being published with this action as a proposed
amendment to appendix B to part 60. The unpublished proposed amendments
are available in Docket A-97-12 or by request from the Air and
Radiation Docket and Information Center (see ADDRESSES) or the EPA
contact person listed in the preceding FOR FURTHER INFORMATION CONTACT
section. The proposed amendments may also be obtained over the Internet
at http://www.epa.gov/oar/oaqps/emc; choose the ``Test Methods'' menu,
then choose ``Proposed Test Methods.'' The amendments will be listed on
the EPA Technology Transfer Network (TTN). The TTN is a network of
electronic bulletin boards developed and operated by the Office of Air
Quality Planning and Standards. The TTN provides information and
technology exchange in various areas of air pollution control. The
service is free, except for the cost of the phone call. Dial (919) 541-
5742 for data transfer of up to a 14,400 bps modem. Select TTN Bulletin
Board: ``Emission Measurement Technical Information Center (EMTIC)''
and select menu item ``Proposed Methods.'' If more information on the
operation of the TTN is needed, contact the systems operator at (919)
541-5384.
VI. Administrative Requirements
A. Docket
The docket is an organized and complete file of all information
submitted to or otherwise considered by EPA in the development of this
proposed rulemaking. The principal purposes of the docket are: (1) To
allow interested parties to identify and locate documents so that they
can effectively participate in the rulemaking process, and (2) to serve
as the record in case of judicial review (except for interagency review
materials) [Clean Air Act Section 307(d)(7)(A)].
B. Office of Management and Budget Review
Under Executive Order 12866 (58 FR 51735 October 4, 1993), EPA is
required to judge whether a regulation is ``significant'' and therefore
subject to Office of Management and Budget (OMB) review and the
requirements of this Executive Order to prepare a regulatory impact
analysis (RIA). The Order defines ``significant regulatory action'' as
one that is likely to result in a rule that may:
(1) Have an annual effect on the economy of $100 million or more or
adversely affect in a material way the economy, a sector of the
economy, productivity, competition, jobs, the environment, public
health or safety, or State, local, or tribal governments or
communities;
(2) Create a serious inconsistency or otherwise interfere with an
action taken or planned by another agency;
(3) Materially alter the budgetary impact of entitlements, grants,
user fees, or loan programs, or the rights and obligation of recipients
thereof; or
(4) Raise novel legal or policy issues arising out of legal
mandates, the President's priorities, or the principles set forth in
the Executive Order. This rulemaking does not impose emission
measurement requirements beyond those specified in the current
regulations, nor does it change any emission standard. The Agency has
determined that this regulation would result in none of the adverse
economic effects set forth in Section 1 of the Order as grounds for
finding the regulation to be a significant rule. The Agency has,
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therefore, concluded that this regulation is not a significant rule
under Executive Order 12866.
C. Regulatory Flexibility Act
The EPA has determined that it is not necessary to prepare a
regulatory flexibility analysis in connection with this proposed rule.
The EPA has also determined that this rule will not have a significant
adverse impact on a substantial number of small businesses. This
rulemaking does not impose emission measurement requirements beyond
those specified in the current regulations, nor does it change any
emission standard. As such, it will not present a significant economic
impact on a substantial number of small businesses.
D. Paperwork Reduction Act
The rule does not impose or change any information collection
requirements subject to OMB review under the Paperwork Reduction Act,
44 U.S.C. 3501 et seq.
E. Unfunded Mandates Reform Act
Under Section 202 of the Unfunded Mandates Reform Act of 1995
(``Unfunded Mandates Act'') signed into law on March 22, 1995, EPA must
prepare a budgetary impact statement to accompany any proposed or final
rule that includes a Federal mandate that may result in estimated costs
to State, local, or tribal governments in the aggregate, or to the
private sector, of $100 million or more. Under Section 205, EPA must
select the most cost-effective and least burdensome alternative that
achieves the objectives of the rule and is consistent with statutory
requirements. Section 203 requires EPA to establish a plan for
informing and advising any small governments that may be significantly
or uniquely impacted by the rule.
The EPA has determined that the action proposed today does not
include a Federal mandate that may result in estimated costs of $100
million or more to either State, local, or tribal governments in the
aggregate, or to the private sector, nor does this action significantly
or uniquely impact small governments, because this action contains no
requirements that apply to such governments or impose obligations upon
them. Therefore, the requirements of the Unfunded Mandates Act do not
apply to this action.
List of Subjects in 40 CFR Part 60
Environmental protection, Air pollution control, New sources, Test
methods and procedures, Performance specifications, Continuous emission
monitors.
40 CFR Part 61
Environmental protection, Air pollution control, Test methods and
procedures.
40 CFR Part 63
Environmental protection, Air pollution control, Hazardous air
pollutants, Test methods and procedures.
Dated: August 18, 1997.
Carol M. Browner,
Administrator.
It is proposed that 40 CFR part 60 be amended as follows:
1. The authority citation for part 60 continues to read as follows:
Authority: 42 U.S.C. 7401, 7411, 7414, 7416, 7601 and 7602.
2. By adding Performance Specification 15 in numerical order to
Appendix B to read as follows:
Appendix B--Performance Specifications
* * * * *
Performance Specification 15--Performance Specification for
Extractive FTIR Continuous Emissions Monitor Systems in Stationary
Sources
1.0 Scope and Application. 1.1 Analytes. This performance
specification is applicable for measuring all hazardous air
pollutants (HAPs) which absorb in the infrared region and can be
quantified using Fourier Transform Infrared Spectroscopy (FTIR), as
long as the performance criteria of this performance specification
are met. This specification is to be used for evaluating FTIR
continuous emission monitoring systems for measuring HAPs regulated
under Title III of the 1990 Clean Air Act Amendments. This
specification also applies to the use of FTIR CEMs for measuring
other volatile organic or inorganic species.
1.2 Applicability. A source which can demonstrate that the
extractive FTIR system meets the criteria of this performance
specification for each regulated pollutant may use the FTIR system
to continuously monitor for the regulated pollutants.
2.0 Summary of Performance Specification. For compound-specific
sampling requirements refer to FTIR sampling methods (e.g.,
reference 1). For data reduction procedures and requirements refer
to the EPA FTIR Protocol (reference 2), hereafter referred to as the
``FTIR Protocol.'' This specification describes sampling and
analytical procedures for quality assurance. The infrared spectrum
of any absorbing compound provides a distinct signature. The
infrared spectrum of a mixture contains the superimposed spectra of
each mixture component. Thus, an FTIR CEM provides the capability to
continuously measure multiple components in a sample using a single
analyzer. The number of compounds that can be speciated in a single
spectrum depends, in practice, on the specific compounds present and
the test conditions.
3.0 Definitions. For a list of definitions related to FTIR
spectroscopy refer to Appendix A of the FTIR Protocol. Unless
otherwise specified, spectroscopic terms, symbols and equations in
this performance specification are taken from the FTIR Protocol or
from documents cited in the Protocol. Additional definitions are
given below.
3.1 FTIR Continuous Emission Monitoring System (FTIR CEM).
3.1.1 FTIR System. Instrument to measure spectra in the mid-
infrared spectral region (500 to 4000 cm -1). It contains
an infrared source, interferometer, sample gas containment cell,
infrared detector, and computer. The interferometer consists of a
beam splitter that divides the beam into two paths, one path a fixed
distance and the other a variable distance. The computer is equipped
with software to run the interferometer and store the raw digitized
signal from the detector (interferogram). The software performs the
mathematical conversion (the Fourier transform) of the interferogram
into a spectrum showing the frequency dependent sample absorbance.
All spectral data can be stored on computer media.
3.1.2 Gas Cell. A gas containment cell that can be evacuated.
It contains the sample as the infrared beam passes from the
interferometer, through the sample, and to the detector. The gas
cell may have multi-pass mirrors depending on the required detection
limit(s) for the application.
3.1.3 Sampling System. Equipment used to extract sample from
the test location and transport the gas to the FTIR analyzer.
Sampling system components include probe, heated line, heated non-
reactive pump, gas distribution manifold and valves, flow
measurement devices and any sample conditioning systems.
3.2 Reference CEM. An FTIR CEM, with sampling system, that can
be used for comparison measurements.
3.3 Infrared Band (also Absorbance Band or Band). Collection of
lines arising from rotational transitions superimposed on a
vibrational transition. An infrared absorbance band is analyzed to
determine the analyte concentration.
3.4 Sample Analysis. Interpreting infrared band shapes,
frequencies, and intensities to obtain sample component
concentrations. This is usually performed by a software routine
using a classical least squares (cls), partial least squares (pls),
or K-or P-matrix method.
3.5 (Target) Analyte. A compound whose measurement is required,
usually to some established limit of detection and analytical
uncertainty.
3.6 Interferant. A compound in the sample matrix whose infrared
spectrum overlaps at least part of an analyte spectrum complicating
the analyte measurement. The interferant may not prevent the analyte
measurement, but could increase the analytical uncertainty in the
measured
[[Page 45373]]
concentration. Reference spectra of interferants are used to
distinguish the interferant bands from the analyte bands. An
interferant for one analyte may not be an interferant for other
analytes.
3.7 Reference Spectrum. Infrared spectra of an analyte, or
interferant, prepared under controlled, documented, and reproducible
laboratory conditions (see Section 4.6 of the FTIR Protocol). A
suitable library of reference spectra can be used to measure target
analytes in gas samples.
3.8 Calibration Spectrum. Infrared spectrum of a compound
suitable for characterizing the FTIR instrument configuration
(Section 4.5 in the FTIR Protocol).
3.9 One hundred percent line. A double beam transmittance
spectrum obtained by combining two successive background single beam
spectra. Ideally, this line is equal to 100 percent transmittance
(or zero absorbance) at every point in the spectrum. The zero
absorbance line is used to measure the RMS noise of the system.
3.10 Background Deviation. Any deviation (from 100 percent) in
the one hundred percent line (or from zero absorbance). Deviations
greater than 5 percent in any analytical region are
unacceptable. Such deviations indicate a change in the instrument
throughput relative to the single-beam background.
3.11 Batch Sampling. A gas cell is alternately filled and
evacuated. A Spectrum of each filled cell (one discreet sample) is
collected and saved.
3.12 Continuous Sampling. Sample is continuously flowing
through a gas cell. Spectra of the flowing sample are collected at
regular intervals.
3.13 Continuous Operation. In continuous operation an FTIR CEM
system, without user intervention, samples flue gas, records spectra
of samples, saves the spectra to a disk, analyzes the spectra for
the target analytes, and prints concentrations of target analytes to
a computer file. User intervention is permitted for initial set-up
of sampling system, initial calibrations, and periodic maintenance.
3.14 Sampling Time. In batch sampling--the time required to
fill the cell with flue gas. In continuous sampling--the time
required to collect the infrared spectrum of the sample gas.
3.15 PPM-Meters. Sample concentration expressed as the
concentration-path length product, ppm (molar) concentration
multiplied by the path length of the FTIR gas cell. Expressing
concentration in these units provides a way to directly compare
measurements made using systems with different optical
configurations. Another useful expression is (ppm-meters)/K, where K
is the absolute temperature of the sample in the gas cell.
3.16 CEM Measurement Time Constant. The Time Constant (TC,
minutes for one cell volume to flow through the cell) determines the
minimum interval for complete removal of an analyte from the FTIR
cell. It depends on the sampling rate (Rs in Lpm), the
FTIR cell volume (Vcell in L) and the chemical and
physical properties of an analyte.
[GRAPHIC] [TIFF OMITTED] TP27AU97.013
For example, if the sample flow rate (through the FTIR cell) is
5 Lpm and the cell volume is 7 liters, then TC is equal to 1.4
minutes (0.71 cell volumes per minute). This performance
specification defines 5 * TC as the minimum interval between
independent samples.
3.17 Independent Measurement. Two independent measurements are
spectra of two independent samples. Two independent samples are
separated by, at least 5 cell volumes. The interval between
independent measurements depends on the cell volume and the sample
flow rate (through the cell). There is no mixing of gas between two
independent samples. Alternatively, estimate the analyte residence
time empirically: (1) Fill cell to ambient pressure with a (known
analyte concentration) gas standard, (2) measure the spectrum of the
gas standard, (3) purge the cell with zero gas at the sampling rate
and collect a spectrum every minute until the analyte standard is no
longer detected spectroscopically. If the measured time corresponds
to less than 5 cell volumes, use 5 * TC as the minimum interval
between independent measurements. If the measured time is greater
than 5 * TC, then use this time as the minimum interval between
independent measurements.
3.18 Test Condition. A period of sampling where all process,
and sampling conditions, and emissions remain constant and during
which a single sampling technique and a single analytical program
are used. One Run may include results for more than one test
condition. Constant emissions means that the composition of the
emissions remains approximately stable so that a single analytical
program is suitable for analyzing all of the sample spectra. A
greater than two-fold change in analyte or interferant
concentrations or the appearance of additional compounds in the
emissions, may constitute a new test condition and may require
modification of the analytical program.
3.19 Run. A single Run consists of spectra (one spectrum each)
of at least 10 independent samples over a minimum of one hour. The
concentration results from the spectra can be averaged together to
give a run average for each analyte measured in the test run.
4.0 Interferences. Several compounds, including water, carbon
monoxide, and carbon dioxide, are known interferences in the
infrared region in which the FTIR instrument operates. Follow the
procedures in the FTIR protocol for subtracting or otherwise dealing
with these and other interferences.
5.0 Safety. The procedures required under this performance
specification may involve hazardous materials, operations, and
equipment. This performance specification does not purport to
address all of the safety problems associated with these procedures.
It is the responsibility of the user to establish appropriate safety
and health practices and determine the applicable regulatory
limitations prior to performing these procedures. The CEMS users
manual and materials recommended by this performance specification
should be consulted for specific precautions to be taken.
6.0 Equipment and Supplies. 6.1 Installation of sampling
equipment should follow requirements of FTIR test Methods such as
references 1 and 3 and the EPA FTIR Protocol (reference 2). Select
test points where the gas stream composition is representative of
the process emissions. If comparing to a reference method, the probe
tips for the FTIR CEM and the RM should be positioned close together
using the same sample port if possible.
6.2 FTIR Specifications. The FTIR CEM must be equipped with
reference spectra bracketing the range of path length-concentrations
(absorbance intensities) to be measured for each analyte. The
effective concentration range of the analyzer can be adjusted by
changing the path length of the gas cell or by diluting the sample.
The optical configuration of the FTIR system must be such that
maximum absorbance of any target analyte is no greater than 1.0 and
the minimum absorbance of any target analyte is at least 10 times
the RMSD noise in the analytical region. For example, if the
measured RMSD in an analytical region is equal to 10-3,
then the peak analyte absorbance is required to be at least 0.01.
Adequate measurement of all of the target analytes may require
changing path lengths during a run, conducting separate runs for
different analytes, diluting the sample, or using more than one gas
cell.
6.3 Data Storage Requirements. The system must have sufficient
capacity to store all data collected in one week of routine
sampling. Data must be stored to a write-protected medium, such as
write-once-read-many (WORM) optical storage medium or to a password
protected remote storage location. A back-up copy of all data can be
temporarily saved to the computer hard drive. The following items
must be stored during testing.
a. At least one sample interferogram per sampling Run or one
interferogram per hour, whichever is greater. This assumes that no
sampling or analytical conditions have changed during the run.
b. All sample absorbance spectra (about 12 per hr, 288 per day).
c. All background spectra and interferograms (variable, but
about 5 per day).
d. All CTS spectra and interferograms (at least 2 each 24 hour
period).
e. Documentation showing a record of resolution, path length,
apodization, sampling time, sampling conditions, and test conditions
for all sample, CTS, calibration, and background spectra.
Using a resolution of 0.5 cm-1, with analytical range
of 3500 cm-1, assuming about 65 Kbytes per spectrum and
130 Kb per interferogram, the storage requirement is about 164 Mb
for one week of continuous sampling. Lower spectral resolution
requires less storage capacity. All of the above data must be stored
for at least two weeks. After two weeks, storage requirements
include: (1) All analytical results (calculated concentrations), (2)
at least 1 sample spectrum with corresponding background and sample
interferograms for each test
[[Page 45374]]
condition, (3) CTS and calibration spectra with at least one
interferogram for CTS and all interferograms for calibrations, (4) a
record of analytical input used to produce results, and (5) all
other documentation. These data must be stored according to the
requirements of the applicable regulation.
7.0 Reagents and Standards. [Reserved]
8.0 Sample Collection, Preservation, Storage, and Transport.
[Reserved]
9.0 Quality Control. These procedures shall be used for
periodic quarterly or semiannual QA/QC checks on the operation of
the FTIR CEM. Some procedures test only the analytical program and
are not intended as a test of the sampling system.
9.1 Audit Sample. This can serve as a check on both the
sampling system and the analytical program.
9.1.1 Sample Requirements. The audit sample can be a mixture or
a single component. It must contain target analyte(s) at
approximately the expected flue gas concentration(s). If possible,
each mixture component concentration should be NIST traceable
(2 percent accuracy). If a cylinder mixture standard(s)
cannot be obtained, then, alternatively, a gas phase standard can be
generated from a condensed phase analyte sample. Audit sample
contents and concentrations are not revealed to the FTIR CEM
operator until after successful completion of procedures in 5.3.2.
9.1.2 Test Procedure. An audit sample is obtained from the
Administrator. Spike the audit sample using the analyte spike
procedure in Section 11. The audit sample is measured directly by
the FTIR system (undiluted) and then spiked into the effluent at a
known dilution ratio. Measure a series of spiked and unspiked
samples using the same procedures as those used to analyze the stack
gas. Analyze the results using Sections 12.1 and 12.2. The measured
concentration of each analyte must be within 5 percent
of the expected concentration (plus the uncertainty), i.e., the
calculated correction factor must be within 0.93 and 1.07 for an
audit with an analyte uncertainty of 2 percent.
9.2 Audit Spectra. Audit spectra can be used to test the
analytical program of the FTIR CEM, but provide no test of the
sampling system.
9.2.1 Definition and Requirements. Audit spectra are absorbance
spectra that: (1) Have been well characterized, and (2) contain
absorbance bands of target analyte(s) and potential interferants at
intensities equivalent to what is expected in the source effluent.
Audit spectra are provided by the administrator without identifying
information. Methods of preparing Audit spectra include: (1)
Mathematically adding sample spectra or adding reference and
interferant spectra, (2) obtaining sample spectra of mixtures
prepared in the laboratory, or (3) they may be sample spectra
collected previously at a similar source. In the last case it must
be demonstrated that the analytical results are correct and
reproducible. A record associated with each Audit spectrum documents
its method of preparation. The documentation must be sufficient to
enable an independent analyst to reproduce the Audit spectra.
9.2.2 Test Procedure. Audit spectra concentrations are measured
using the FTIR CEM analytical program. Analytical results must be
within 5 percent of the certified audit concentration
for each analyte (plus the uncertainty in the audit concentration).
If the condition is not met, demonstrate how the audit spectra are
unrepresentative of the sample spectra. If the audit spectra are
representative, modify the FTIR CEM analytical program until the
test requirement is met. Use the new analytical program in
subsequent FTIR CEM analyses of effluent samples.
9.3 Submit Spectra For Independent Analysis. This procedure
tests only the analytical program and not the FTIR CEM sampling
system. The analyst can submit FTIR CEM spectra for independent
analysis by EPA. Requirements for submission include: (1) Three
representative absorbance spectra (and stored interferograms) for
each test period to be reviewed, (2) corresponding CTS spectra, (3)
corresponding background spectra and interferograms, (4) spectra of
associated spiked samples if applicable, and (5) analytical results
for these sample spectra. The analyst will also submit documentation
of process times and conditions, sampling conditions associated with
each spectrum, file names and sampling times, method of analysis and
reference spectra used, optical configuration of FTIR CEM including
cell path length and temperature, spectral resolution and
apodization used for every spectrum. Independent analysis can also
be performed on site in conjunction with the FTIR CEM sampling and
analysis. Sample spectra are stored on the independent analytical
system as they are collected by the FTIR CEM system. The FTIR CEM
and the independent analyses are then performed separately. The two
analyses will agree to within 20 percent for each
analyte using the procedure in Section 12.3. This assumes both
analytical routines have properly accounted for differences in
optical path length, resolution, and temperature between the sample
spectra and the reference spectra.
10.0 Calibration/Standardization.
10.1 Calibration Transfer Standards. For CTS requirements see
Section 4.5 of the FTIR Protocol. A well characterized absorbance
band in the CTS gas is used to measure the path length and line
resolution of the instrument. The CTS measurements made at the
beginning of every 24 hour period must agree to within 5
percent after correction for differences in pressure. Verify that
the frequency response of the instrument and CTS absorbance
intensity are correct by comparing to other CTS spectra or by
referring to the literature.
10.2 Analyte Calibration. If EPA library reference spectra are
not available, use calibration standards to prepare reference
spectra according to Section 6 of the FTIR Protocol. A suitable set
of analyte reference data includes spectra of at least 2 independent
samples at each of at least 2 different concentrations. The
concentrations bracket a range that includes the expected analyte
absorbance intensities. The linear fit of the reference analyte band
areas must have a fractional calibration uncertainty (FCU in
Appendix F of the FTIR Protocol) of no greater than 10 percent. For
requirements of analyte standards refer to Section 4.6 of the FTIR
Protocol.
10.3 System Calibration. The calibration standard is introduced
at a point on the sampling probe. The sampling system is purged with
the calibration standard to verify that the absorbance measured in
this way is equal to the absorbance in the analyte calibration. Note
that the system calibration gives no indication of the ability of
the sampling system to transport the target analyte(s) under the
test conditions.
10.4 Analyte Spike. The target analyte(s) is spiked at the
outlet of the sampling probe, upstream of the particulate filter,
and combined with effluent at a ratio of about 1 part spike to 9
parts effluent. The measured absorbance of the spike is compared to
the expected absorbance of the spike plus the analyte concentration
already in the effluent. This measures sampling system bias, if any,
as distinguished from analyzer bias. It is important that spiked
sample pass through all of the sampling system components before
analysis.
10.5 Signal-to-Noise Ratio (S/N). The measure of S/N in this
performance specification is the root-mean-square (RMS) noise level
as given in Appendix C of the FTIR Protocol. The RMS noise level of
a contiguous segment of a spectrum is defined as the RMS difference
(RMSD) between the n contiguous absorbance values (Ai)
which form the segment and the mean value (AM) of that
segment.
[GRAPHIC] [TIFF OMITTED] TP27AU97.014
A decrease in the S/N may indicate a loss in optical throughput,
or detector or interferometer malfunction.
10.6 Background Deviation. The 100 percent baseline must be
between 95 and 105 percent transmittance (absorbance of 0.02 to
-0.02) in every analytical region. When background deviation exceeds
this range, a new background spectrum must be collected using
nitrogen or other zero gas.
10.7 Detector Linearity. Measure the background and CTS at
three instrument aperture settings; one at the aperture setting to
be used in the testing, and one each at settings one half and twice
the test aperture setting. Compare the three CTS spectra. CTS band
areas should agree to within the uncertainty of the cylinder
standard. If test aperture is the maximum aperture, collect CTS
spectrum at maximum aperture, then close the aperture to reduce the
IR through-put by half. Collect a second background and CTS at the
smaller aperture setting and compare the spectra as above. Instead
of changing the aperture neutral density filters can be used to
attenuate the infrared beam. Set up the FTIR system as it will be
used in the test measurements. Collect a CTS spectrum. Use a neutral
density filter to attenuate the infrared beam (either immediately
after the source or the interferometer) to approximately \1/2\ its
original intensity. Collect a second CTS spectrum. Use another
filter to attenuate the infrared beam to approximately \1/4\ its
original intensity. Collect a third background
[[Page 45375]]
and CTS spectrum. Compare the CTS spectra as above. Another check on
linearity is to observe the single beam background in frequency
regions where the optical configuration is known to have a zero
response. Verify that the detector response is ``flat'' and equal to
zero in these regions. If detector response is not linear, decrease
aperture, or attenuate the infrared beam. Repeat the linearity check
until system passes the requirement.
11.0 Analytical Procedure.
11.1 Initial Certification. First, perform the evaluation
procedures in Section 6.0 of the FTIR Protocol. The performance of
an FTIR CEM can be certified upon installation using EPA Method 301
type validation (40 CFR, Part 63, Appendix A), or by comparison to a
reference Method if one exists for the target analyte(s). Details of
each procedure are given below. Validation testing is used for
initial certification upon installation of a new system. Subsequent
performance checks can be performed with more limited analyte
spiking. Performance of the analytical program is checked initially,
and periodically as required by EPA, by analyzing audit spectra or
audit gases.
11.1.1 Validation. Use EPA Method 301 type sampling (reference
4, Section 5.3 of Method 301) to validate the FTIR CEM for measuring
the target analytes. The analyte spike procedure is as follows: (1)
A known concentration of analyte is mixed with a known concentration
of a non-reactive tracer gas, (2) the undiluted spike gas is sent
directly to the FTIR cell and a spectrum of this sample is
collected, (3) pre-heat the spiked gas to at least the sample line
temperature, (4) introduce spike gas at the back of the sample probe
upstream of the particulate filter, (5) spiked effluent is carried
through all sampling components downstream of the probe, (6) spike
at a ratio of roughly 1 part spike to 9 parts flue gas (or more
dilute), (7) the spike-to-flue gas ratio is estimated by comparing
the spike flow to the total sample flow, and (8) the spike ratio is
verified by comparing the tracer concentration in spiked flue gas to
the tracer concentration in undiluted spike gas. The analyte flue
gas concentration is unimportant as long as the spiked component can
be measured and the sample matrix (including interferences) is
similar to its composition under test conditions. Validation can be
performed using a single FTIR CEM analyzing sample spectra collected
sequentially. Since flue gas analyte (unspiked) concentrations can
vary, it is recommended that two separate sampling lines (and pumps)
are used; one line to carry unspiked flue gas and the other line to
carry spiked flue gas. Even with two sampling lines the variation in
unspiked concentration may be fast compared to the interval between
consecutive measurements. Alternatively, two FTIR CEMs can be
operated side-by-side, one measuring spiked sample, the other
unspiked sample. In this arrangement spiked and unspiked
measurements can be synchronized to minimize the affect of temporal
variation in the unspiked analyte concentration. In either sampling
arrangement, the interval between measured concentrations used in
the statistical analysis should be, at least, 5 cell volumes (5 * TC
in equation 1). A validation run consists of, at least, 24
independent analytical results, 12 spiked and 12 unspiked samples.
See Section 3.17 for definition of an ``independent'' analytical
result. The results are analyzed using Sections 12.1 and 12.2 to
determine if the measurements passed the validation requirements.
Several analytes can be spiked and measured in the same sampling
run, but a separate statistical analysis is performed for each
analyte. In lieu of 24 independent measurements, averaged results
can be used in the statistical analysis. In this procedure, a series
of consecutive spiked measurements are combined over a sampling
period to give a single average result. The related unspiked
measurements are averaged in the same way. The minimum 12 spiked and
12 unspiked result averages are obtained by averaging measurements
over subsequent sampling periods of equal duration. The averaged
results are grouped together and statistically analyzed using
Section 12.2.
11.1.1.1 Validation with a Single Analyzer and Sampling Line.
If one sampling line is used, connect the sampling system components
and purge the entire sampling system and cell with at least 10 cell
volumes of sample gas. Begin sampling by collecting spectra of 2
independent unspiked samples. Introduce the spike gas into the back
of the probe, upstream of the particulate filter. Allow 10 cell
volumes of spiked flue gas to purge the cell and sampling system.
Collect spectra of 2 independent spiked samples. Turn off the spike
flow and allow 10 cell volumes of unspiked flue gas to purge the
FTIR cell and sampling system. Repeat this procedure 6 times until
the 24 samples are collected. Spiked and unspiked samples can also
be measured in groups of 4 instead of in pairs. Analyze the results
using Sections 12.1 and 12.2. If the statistical analysis passes the
validation criteria, then the validation is completed. If the
results do not pass the validation, the cause may be that temporal
variations in the analyte sample gas concentration are fast relative
to the interval between measurements. The difficulty may be avoided
by: (1) Averaging the measurements over long sampling periods and
using the averaged results in the statistical analysis, (2)
modifying the sampling system to reduce TC by, for example, using a
smaller volume cell or increasing the sample flow rate, (3) using
two sample lines (4) use two analyzers to perform synchronized
measurements. This performance specification permits modifications
in the sampling system to minimize TC if the other requirements of
the validation sampling procedure are met.
11.1.1.2 Validation With a Single Analyzer and Two Sampling
Lines. An alternative sampling procedure uses two separate sample
lines, one carrying spiked flue gas, the other carrying unspiked
gas. A valve in the gas distribution manifold allows the operator to
choose either sample. A short heated line connects the FTIR cell to
the 3-way valve in the manifold. Both sampling lines are
continuously purged. Each sample line has a rotameter and a bypass
vent line after the rotameter, immediately upstream of the valve, so
that the spike and unspiked sample flows can each be continuously
monitored. Begin sampling by collecting spectra of 2 independent
unspiked samples. Turn the sampling valve to close off the unspiked
gas flow and allow the spiked flue gas to enter the FTIR cell.
Isolate and evacuate the cell and fill with the spiked sample to
ambient pressure. (While the evacuated cell is filling, prevent air
leaks into the cell by making sure that the spike sample rotameter
always indicates that a portion of the flow is directed out the by-
pass vent.) Open the cell outlet valve to allow spiked sample to
continuously flow through the cell. Measure spectra of 2 independent
spiked samples. Repeat this procedure until at least 24 samples are
collected.
11.1.1.3 Synchronized Measurements With Two Analyzers. Use two
FTIR analyzers, each with its own cell, to perform synchronized
spiked and unspiked measurements. If possible, use a similar optical
configuration for both systems. The optical configurations are
compared by measuring the same CTS gas with both analyzers. Each
FTIR system uses its own sampling system including a separate
sampling probe and sampling line. A common gas distribution manifold
can be used if the samples are never mixed. One sampling system and
analyzer measures spiked effluent. The other sampling system and
analyzer measures unspiked flue gas. The two systems are
synchronized so that so that each measures spectra at approximately
the same times. The sample flow rates are also synchronized so that
both sampling rates are approximately the same (TC1 TC2
in equation 1). Start both systems at the same time. Collect spectra
of at least 12 independent samples with each (spiked and unspiked)
system to obtain the minimum 24 measurements. Analyze the analytical
results using Sections 12.1 and 12.2. Run averages can be used in
the statistical analysis instead of individual measurements.
11.1.1.4 Compare to a Reference Method (RM). Obtain EPA
approval that the method qualifies as an RM for the analyte(s) and
the source to be tested. Follow the published procedures for the RM
in preparing and setting up equipment and sampling system,
performing measurements, and reporting results. Since FTIR CEMS have
multicomponent capability, it is possible to perform more than one
RM simultaneously, one for each target analyte. Conduct at least 9
runs where the FTIR CEM and the RM are sampling simultaneously. Each
Run is at least 30 minutes long and consists of spectra of at least
5 independent FTIR CEM samples and the corresponding RM
measurements. If more than 9 runs are conducted, the analyst may
eliminate up to 3 runs from the analysis if at least 9 runs are
used.
11.1.1.4.1 RMs Using Integrated Sampling. Perform the RM and
FTIR CEM sampling simultaneously. The FTIR CEM can measure spectra
as frequently as the analyst chooses (and should obtain measurements
as frequently as possible) provided that the measurements include
spectra of at least 5 independent measurements every 30 minutes.
Concentration results from all of the FTIR CEM spectra within a run
may be averaged for use in the statistical comparison
[[Page 45376]]
even if all of the measurements are not independent. When averaging
the FTIR CEM concentrations within a run, it is permitted to exclude
some measurements from the average provided the minimum of 5
independent measurements every 30 minutes are included: The Run
average of the FTIR CEM measurements depends on both the sample flow
rate and the measurement frequency (MF). The run average of the RM
using the integrated sampling method depends primarily on its
sampling rate. If the target analyte concentration fluctuates
significantly, the contribution to the run average of a large
fluctuation depends on the sampling rate and measurement frequency,
and on the duration and magnitude of the fluctuation. It is,
therefore, important to carefully select the sampling rate for both
the FTIR CEM and the RM and the measurement frequency for the FTIR
CEM. The minimum of 9 run averages can be compared according to the
relative accuracy test procedure in Performance Specification 2 for
SO2 and NOX CEMs (40 CFR part 60, Appendix B).
11.1.1.4.2 RMs Using a Grab Sampling Technique. Synchronize the
RM and FTIR CEM measurements as closely as possible. For a grab
sampling RM record the volume collected and the exact sampling
period for each sample. Synchronize the FTIR CEM so that the FTIR
measures a spectrum of a similar cell volume at the same time as the
RM grab sample was collected. Measure at least 5 independent samples
with both the FTIR CEM and the RM for each of the minimum 9 Runs.
Compare the Run concentration averages by using the relative
accuracy analysis procedure in 40 CFR part 60, Appendix B.
11.1.1.4.3 Continuous Emission Monitors (CEMs) as RMs. If the
RM is a CEM, synchronize the sampling flow rates of the RM and the
FTIR CEM. Each run is at least 1-hour long and consists of at least
10 FTIR CEM measurements and the corresponding 10 RM measurements
(or averages). For the statistical comparison use the relative
accuracy analysis procedure in 40 CFR part 60, Appendix B. If the RM
time constant is < \1/2\="" the="" ftir="" cem="" time="" constant,="" brief="" fluctuations="" in="" analyte="" concentrations="" which="" are="" not="" adequately="" measured="" with="" the="" slower="" ftir="" cem="" time="" constant="" can="" be="" excluded="" from="" the="" run="" average="" along="" with="" the="" corresponding="" rm="" measurements.="" however,="" the="" ftir="" cem="" run="" average="" must="" still="" include="" at="" least="" 10="" measurements="" over="" a="" 1-hr="" period.="" 12.0="" calculations="" and="" data="" analysis.="" 12.1="" spike="" dilution="" ratio,="" expected="" concentration.="" the="" method="" 301="" bias="" is="" calculated="" as="" follows.="" b="">m--Mm--CS
Where
B=Bias at the spike level
Sm=Mean of the observed spiked sample concentrations
Mm=Mean of the observed unspiked sample concentrations
CS=Expected value of the spiked concentration. The CS is determined
by comparing the SF6 tracer concentration in undiluted
spike gas to the SF6 tracer concentrations in the spiked
samples;
[GRAPHIC] [TIFF OMITTED] TP27AU97.015
The expected concentration (CS) is the measured concentration of
the analyte in undiluted spike gas divided by the dilution factor
[GRAPHIC] [TIFF OMITTED] TP27AU97.016
where
[anal]dir=The analyte concentration in undiluted spike
gas measured directly by filling the FTIR cell with the spike gas.
If the bias is statistically significant (Section 12.2), Method 301
requires that a correction factor, CF, be multiplied by the
analytical results, and that 0.7 CF 1.3.
[GRAPHIC] [TIFF OMITTED] TP27AU97.017
12.2 Statistical Analysis of Validation Measurements. Arrange the
independent measurements (or measurement averages) as in Table 1.
More than 12 pairs of measurements can be analyzed. The statistical
analysis follows EPA Method 301, Section 6.3. Section 12.1 of this
performance specification shows the calculations for the bias,
expected spike concentration, and correction factor. This Sections
shows the determination of the statistical significance of the bias.
Determine the statistical significance of the bias at the 95 percent
confidence level by calculating the t-value for the set of
measurements. First, calculate the differences, di, for
each pair of spiked and each pair of unspiked measurements. Then
calculate the standard deviation of the spiked pairs of
measurements.
[GRAPHIC] [TIFF OMITTED] TP27AU97.018
Where
di=The differences between pairs of spiked measurements.
SDs=The standard deviation in the di values.
n=The number of spiked pairs, 2n=12 for the minimum of 12 spiked and
12 unspiked measurements.
Calculate the relative standard deviation, RSD, using
SDs and the mean of the spiked concentrations,
Sm. The RSD must be 50%.
[GRAPHIC] [TIFF OMITTED] TP27AU97.019
Repeat the calculations in equations 7 and 8 to determine
SDu and RSD, respectively, for the unspiked samples.
Calculate the standard deviation of the mean using
SDs and SDu from equation 7.
[GRAPHIC] [TIFF OMITTED] TP27AU97.020
The t-statistic is calculated as follows to test the bias for
statistical significance;
[GRAPHIC] [TIFF OMITTED] TP27AU97.021
Where the bias, B, and the correction factor, CF, are given in
Section 12.1.
For 11 degrees of freedom, and a one-tailed distribution, Method
301 requires that t 2.201. If the t-statistic indicates
the bias is statistically significant, then analytical measurements
must be multiplied by the correction factor. There is no limitation
on the number of measurements, but there must be at least 12
independent spiked and 12 independent unspiked measurements. Refer
to the t-distribution (Table 2) at the 95 percent confidence level
and appropriate degrees of freedom for the critical t-value.
13.0-15.0 [Reserved]
16.0 References.
1. Method 318, 40 CFR Part 63, Appendix A (Draft), ``Measurement
of Gaseous Formaldehyde, Phenol and Methanol Emissions by FTIR
Spectroscopy,'' EPA Contract No. 68D20163, Work Assignment 2-18,
February, 1995.
2. ``EPA Protocol for the Use of Extractive Fourier Transform
Infrared (FTIR) Spectrometry in Analyses of Gaseous Emissions from
Stationary Industrial Sources,'' February, 1995.
3. ``Measurement of Gaseous Organic and Inorganic Emissions by
Extractive FTIR Spectroscopy,'' EPA Contract No. 68-D2-0165, Work
Assignment 3-08.
4. ``Method 301--Field Validation of Pollutant Measurement
Methods from Various Waste Media,'' 40 Part CFR 63, Appendix A.
17.0 Tables, Diagrams, Flowcharts, and Validation Data.
Table 1.--Arrangement of Validation Measurements For Statistical Analysis.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Measurement (or average) Time Spiked (ppm) di spiked Unspiked (ppm) di unspiked
--------------------------------------------------------------------------------------------------------------------------------------------------------
1................................... ........... S1 ........................ U1 .......................
2................................... ........... S2 S2-S1 U2 U2-U1
3................................... ........... S3 ........................ U3 .......................
4................................... ........... S4 S4-S3 U4 U4-U3
[[Page 45377]]
5................................... ........... S5 ........................ U5 .......................
6................................... ........... S6 S6-S5 U6 U6-U5
7................................... ........... S7 ........................ U7 .......................
8................................... ........... S8 S8-S7 U8 U8-U7
9................................... ........... S9 ........................ U9 .......................
10.................................. ........... S10 S10-S9 U10 U10-U9
11.................................. ........... S11 ........................ U11 .......................
12.................................. ........... S12 S12-S11 U12 U12-U11
Average->........................... ........... Sm ........................ Mm .......................
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table 2.--t-Values
----------------------------------------------------------------------------------------------------------------
n-1a t-value n-1a t-value n-1a t-value n-1a t-value
----------------------------------------------------------------------------------------------------------------
11.......... 2.201 17 2.110 23 2.069 29 2.045
12.......... 2.179 18 2.101 24 2.064 30 2.042
13.......... 2.160 19 2.093 25 2.060 40 2.021
14.......... 2.145 20 2.086 26 2.056 60 2.000
15.......... 2.131 21 2.080 27 2.052 120 1.980
16.......... 2.120 22 2.074 28 2.048 1.960
----------------------------------------------------------------------------------------------------------------
(a) n is the number of independent pairs of measurements (a pair consists of one spiked and its corresponding
unspiked measurement). Either discreet (independent) measurements in a single run, or run averages can be
used.
[FR Doc. 97-22508 Filed 8-26-97; 8:45 am]
BILLING CODE 6560-50-P
