§ 1.924 - Quiet zones.

§ 1.924 Quiet zones.

Areas implicated by this paragraph are those in which it is necessary to restrict radiation so as to minimize possible impact on the operations of radio astronomy or other facilities that are highly sensitive to interference. Consent throughout this paragraph means written consent from the quiet zone, radio astronomy, research, and receiving installation entity. The areas involved and procedures required are as follows:

(a) NRAO, NRRO. The requirements of this paragraph are intended to minimize possible interference at the National Radio Astronomy Observatory site located at Green Bank, Pocahontas County, West Virginia, and at the Naval Radio Research Observatory site at Sugar Grove, Pendleton County, West Virginia.

(1) Applicants and licensees planning to construct and operate a new or modified station at a permanent fixed location within the area bounded by N 39°15′0.4″ on the north, W 78°29′59.0″ on the east, N 37°30′0.4″ on the south, and W 80°29′59.2″ on the west must notify the Director, National Radio Astronomy Observatory, Post Office Box No. 2, Green Bank, West Virginia 24944, in writing, of the technical details of the proposed operation. The notification must include the geographical coordinates of the antenna location, the antenna height, antenna directivity (if any), the channel, the emission type and power.

(2) When an application for authority to operate a station is filed with the FCC, the notification required in paragraph (a)(1) of this section may be made prior to, or simultaneously with the application. The application must state the date that notification in accordance with paragraph (a)(1) of this section was made. After receipt of such applications, the FCC will allow a period of 20 days for comments or objections in response to the notifications indicated. If an applicant submits written consent from the National Radio Astronomy Observatory for itself or on behalf of the Naval Radio Research Observatory, the FCC will process the application without awaiting the conclusion of the 20-day period. For services that do not require individual station authorization, entities that have obtained written consent from the National Radio Astronomy Observatory for itself or on behalf of the Naval Radio Research Observatory may begin to operate new or modified facilities prior to the end of the 20-day period. In instances in which notification has been made to the National Radio Astronomy Observatory prior to application filing, the applicant must also provide notice to the quiet zone entity upon actual filing of the application with the FCC. Such notice will be made simultaneous with the filing of the application and shall comply with the requirements of paragraph (a)(1) of this section.

(3) If an objection is received during the 20-day period from the National Radio Astronomy Observatory for itself or on behalf of the Naval Radio Research Observatory, the FCC will, after consideration of the record, take whatever action is deemed appropriate.

(b) Table Mountain. The requirements of this paragraph are intended to minimize possible interference at the Table Mountain Radio Receiving Zone of the Research Laboratories of the Department of Commerce located in Boulder County, Colorado.

(1) Licensees and applicants planning to construct and operate a new or modified station at a permanent fixed location in the vicinity of Boulder County, Colorado are advised to give consideration, prior to filing applications, to the need to protect the Table Mountain Radio Receiving Zone from interference. To prevent degradation of the present ambient radio signal level at the site, the Department of Commerce seeks to ensure that the field strengths of any radiated signals (excluding reflected signals) received on this 1800 acre site (in the vicinity of coordinates 40°07′49.9″ North Latitude, 105°14′42.0″ West Longitude) resulting from new assignments (other than mobile stations) or from the modification or relocation of existing facilities do not exceed the values given in the following table:

Field Strength Limits for Table Mountain¹

Frequency range	Field strength (mV/m)	Power flux density (dBW/m2)
Below 540 kHz	10	−65.8
540 to 1600 kHz	20	−59.8
1.6 to 470 MHz	10	−65.8
470 to 890 MHz	30	−56.2
890 MHz and above	1	−85.8

¹ Note: Equivalent values of power flux density are calculated assuming free space characteristic impedance of 376.7Ω (120πΩ).

(2) Advance consultation is recommended, particularly for applicants that have no reliable data to indicate whether the field strength or power flux density figures in the above table would be exceeded by their proposed radio facilities. In general, coordination is recommended for:

(i) Stations located within 2.4 kilometers (1.5 miles) of the Table Mountain Radio Receiving Zone;

(ii) Stations located within 4.8 kilometers (3 miles) transmitting with 50 watts or more effective radiated power (ERP) in the primary plane of polarization in the azimuthal direction of the Table Mountain Radio Receiving Zone;

(iii) Stations located with 16 kilometers (10 miles) transmitting with 1 kW or more ERP in the primary plane of polarization in the azimuthal direction of Table Mountain Radio Receiving Zone;

(iv) Stations located within 80 kilometers (50 miles) transmitting with 25 kW or more ERP in the primary plane of polarization in the azimuthal direction of Table Mountain Receiving Zone.

(3) Applicants concerned are urged to communicate with the Radio Frequency Manager, Department of Commerce, 325 Broadway, Boulder, CO 80305; Telephone: [phone], Fax: [phone], E-mail: [e-mail], in advance of filing their applications with the Commission.

(4) The FCC will not screen applications to determine whether advance consultation has taken place. However, such consultation may avoid the filing of objections from the Department of Commerce or institution of proceedings to modify the authorizations of stations that radiate signals with a field strength or power flux density at the site in excess of those specified herein.

(c) Federal Communications Commission protected field offices. The requirements of this paragraph are intended to minimize possible interference to FCC monitoring activities.

(1) Licensees and applicants planning to construct and operate a new or modified station at a permanent fixed location in the vicinity of an FCC protected field office are advised to give consideration, prior to filing applications, to the need to avoid interfering with the monitoring activities of that office. FCC protected field offices are listed in § 0.121 of this chapter.

(2) Applications for stations (except mobile stations) that could produce on any channel a direct wave fundamental field strength of greater than 10 mV/m (−65.8 dBW/m² power flux density assuming a free space characteristic impedance of 120π Ω) in the authorized bandwidth at the protected field office may be examined to determine the potential for interference with monitoring activities. After consideration of the effects of the predicted field strength of the proposed station, including the cumulative effects of the signal from the proposed station with other ambient radio field strength levels at the protected field office, the FCC may add a condition restricting radiation toward the protected field office to the station authorization.

(3) In the event that the calculated field strength exceeds 10 mV/m at the protected field office site, or if there is any question whether field strength levels might exceed that level, advance consultation with the FCC to discuss possible measures to avoid interference to monitoring activities should be considered. Prospective applicants may communicate with: Chief, Enforcement Bureau, Federal Communications Commission, Washington, DC 20554.

(4) Advance consultation is recommended for applicants that have no reliable data to indicate whether the field strength or power flux density figure indicated would be exceeded by their proposed radio facilities. In general, coordination is recommended for:

(i) Stations located within 2.4 kilometers (1.5 miles) of the protected field office;

(ii) Stations located within 4.8 kilometers (3 miles) with 50 watts or more average effective radiated power (ERP) in the primary plane of polarization in the azimuthal direction of the protected field offices.

(iii) Stations located within 16 kilometers (10 miles) with 1 kw or more average ERP in the primary plane of polarization in the azimuthal direction of the protected field office;

(iv) Stations located within 80 kilometers (50 miles) with 25 kw or more average ERP in the primary plane of polarization in the azimuthal direction of the protected field office;

(v) Advance coordination for stations transmitting on channels above 1000 MHz is recommended only if the proposed station is in the vicinity of a protected field office designated as a satellite monitoring facility in § 0.121 of this chapter.

(vi) The FCC will not screen applications to determine whether advance consultation has taken place. However, such consultation may serve to avoid the need for later modification of the authorizations of stations that interfere with monitoring activities at protected field offices.

(d) Notification to the Arecibo Observatory. The requirements in this section are intended to minimize possible interference at the Arecibo Observatory in Puerto Rico. Licensees must make reasonable efforts to protect the Observatory from interference. Licensees planning to construct and operate a new station at a permanent fixed location on the islands of Puerto Rico, Desecheo, Mona, Vieques or Culebra in services in which individual station licenses are issued by the FCC; planning to construct and operate a new station at a permanent fixed location on these islands that may cause interference to the operations of the Arecibo Observatory in services in which individual station licenses are not issued by the FCC; or planning a modification of any existing station at a permanent fixed location on these islands that would increase the likelihood of causing interference to the operations of the Arecibo Observatory must notify the Interference Office, Arecibo Observatory, HC3 Box 53995, Arecibo, Puerto Rico 00612, in writing or electronically (e-mail address: [e-mail]), of the technical parameters of the planned operation. Carriers may wish to use the interference guidelines provided by Cornell University as guidance in designing facilities to avoid interference to the Observatory. The notification must include identification of the geographical coordinates of the antenna location (NAD-83 datum), the antenna height, antenna directivity (if any), proposed channel and FCC Rule Part, type of emission, and effective isotropic radiated power.

(1) In the Amateur radio service:

(i) The provisions of paragraph (d) of this section do not apply to repeaters that transmit on the 1.2 cm or shorter wavelength bands; and

(ii) The coordination provision of paragraph (d) of this section does not apply to repeaters that are located 16 km or more from the Arecibo observatory.

(2) In services in which individual station licenses are issued by the FCC, the notification required in paragraph (d) of this section may be made prior to, or simultaneously with, the filing of the application with the FCC, and at least 20 days in advance of the applicant's planned operation. The application must state the date that notification in accordance with paragraph (d) of this section was made. In services in which individual station licenses are not issued by the FCC, the notification required in paragraph (d) of this section should be sent at least 45 days in advance of the applicant's planned operation. In the latter services, the Interference Office must inform the FCC of a notification by an applicant within 20 days if the Office plans to file comments or objections to the notification. After the FCC receives an application from a service applicant or is informed by the Interference Office of a notification from a service applicant, the FCC will allow the Interference Office a period of 20 days for comments or objections in response to the application or notification. If an applicant submits written consent from the Interference Office, the FCC will process the application without awaiting the conclusion of the 20-day period. For services that do not require individual station authorization, entities that have obtained written consent from the Interference Office may begin to operate new or modified facilities prior to the end of the 20-day period. In instances in which notification has been made to the Interference Office prior to application filing, the applicant must also provide notice to the Interference Office upon actual filing of the application with the FCC. Such notice will be made simultaneous with the filing of the application and shall comply with the requirements of paragraph (d) of this section.

(3) If an objection to any planned service operation is received during the 20-day period from the Interference Office, the FCC will take whatever action is deemed appropriate.

(4) The provisions of paragraph (d) of this section do not apply to operations that transmit on frequencies above 15 GHz.

(e) 420-450 MHz band. Applicants for pulse-ranging radiolocation systems operating in the 420-450 MHz band along the shoreline of the conterminous United States and Alaska, and for spread spectrum radiolocation systems operating in the 420-435 MHz sub-band within the conterminous United States and Alaska, should not expect to be accommodated if their area of service is within:

(1) Arizona, Florida, or New Mexico;

(2) Those portions of California and Nevada that are south of latitude 37°10′ N.;

(3) That portion of Texas that is west of longitude 104° W.; or

(4) The following circular areas:

(i) 322 kilometers (km) of 30°30′ N., 86°30′ W.

(ii) 322 km of 28°21′ N., 80°43′ W.

(iii) 322 km of 34°09′ N., 119°11′ W.

(iv) 240 km of 39°08′ N., 121°26′ W.

(v) 200 km of 31°25′ N., 100°24′ W.

(vi) 200 km of 32°38′ N., 83°35′ W.

(vii) 160 km of 64°17′ N., 149°10′ W.

(viii) 160 km of 48°43′ N., 97°54′ W.

(ix) 160 km of 41°45′ N., 70°32′ W.

(f) 17.7-19.7 GHz band. The following exclusion areas and coordination areas are established to minimize or avoid harmful interference to Federal Government earth stations receiving in the 17.7-19.7 GHz band:

(1) No application seeking authority for fixed stations, under parts 74, 78, or 101 of this chapter, supporting the operations of Multichannel Video Programming Distributors (MVPD) in the 17.7-17.8 GHz band or to operate in the 17.8-19.7 GHz band for any service will be accepted for filing if the proposed station is located within 20 km (or within 55 km if the modification application is for an outdoor low power operation pursuant to § 101.147(r)(14) of this chapter) of Denver, CO (39°43′ N., 104°46′ W.) or Washington, DC (38°48′ N., 76°52′ W.).

(2) Any application for a new station license to provide MVPD operations in the 17.7-17.8 GHz band or to operate in the 17.8-19.7 GHz band for any service, or for modification of an existing station license in these bands which would change the frequency, power, emission, modulation, polarization, antenna height or directivity, or location of such a station, must be coordinated with the Federal Government by the Commission before an authorization will be issued, if the station or proposed station is located in whole or in part within any of the following areas:

(i) Denver, CO area:

(A) Between latitudes 41°30′ N. and 38°30′ N. and between longitudes 103°10′ W. and 106°30′ W.

(B) Between latitudes 38°30′ N. and 37°30′ N. and between longitudes 105°00′ W. and 105°50′ W.

(C) Between latitudes 40°08′ N. and 39°56′ N. and between longitudes 107°00′ W. and 107°15′ W.

(ii) Washington, DC area:

(A) Between latitudes 38°40′ N. and 38°10′ N. and between longitudes 78°50′ W. and 79°20′ W.

(B) Within 178 km of 38°48′ N., 76°52′ W.

(iii) San Miguel, CA area:

(A) Between latitudes 34°39′ N. and 34°00′ N. and between longitudes 118°52′ W. and 119°24′ W.

(B) Within 200 km of 35°44′ N., 120°45′ W.

(iv) Guam area: Within 100 km of 13°35′ N., 144°51′ E.

Note to § 1.924(f): The coordinates cited in this section are specified in terms of the “North American Datum of 1983 (NAD 83).”

(g) GOES. The requirements of this paragraph are intended to minimize harmful interference to Geostationary Operational Environmental Satellite earth stations receiving in the band 1670-1675 MHz, which are located at Wallops Island, Virginia; Fairbanks, Alaska; and Greenbelt, Maryland.

(1) Applicants and licensees planning to construct and operate a new or modified station within the area bounded by a circle with a radius of 100 kilometers (62.1 miles) that is centered on 37°56′44″ N, 75°27′37″ W (Wallops Island) or 64°58′22″ N, 147°30′04″ W (Fairbanks) or within the area bounded by a circle with a radius of 65 kilometers (40.4 miles) that is centered on 39°00′02″ N, 76°50′29″ W (Greenbelt) must notify the National Oceanic and Atmospheric Administration (NOAA) of the proposed operation. For this purpose, NOAA maintains the GOES coordination Web page at http://www.osd.noaa.gov/radio/frequency.htm, which provides the technical parameters of the earth stations and the point-of-contact for the notification. The notification shall include the following information: Requested frequency, geographical coordinates of the antenna location, antenna height above mean sea level, antenna directivity, emission type, equivalent isotropically radiated power, antenna make and model, and transmitter make and model.

(2) Protection.

(i) Wallops Island and Fairbanks. Licensees are required to protect the Wallops Island and Fairbanks sites at all times.

(ii) Greenbelt. Licensees are required to protect the Greenbelt site only when it is active. Licensees should coordinate appropriate procedures directly with NOAA for receiving notification of times when this site is active.

(3) When an application for authority to operate a station is filed with the FCC, the notification required in paragraph (f)(1) of this section should be sent at the same time. The application must state the date that notification in accordance with paragraph (f)(1) of this section was made. After receipt of such an application, the FCC will allow a period of 20 days for comments or objections in response to the notification.

(4) If an objection is received during the 20-day period from NOAA, the FCC will, after consideration of the record, take whatever action is deemed appropriate.

Note to § 1.924:

Unless otherwise noted, all coordinates cited in this section are specified in terms of the North American Datum of 1983 (NAD 83).

[63 FR 68924, Dec. 14, 1998, as amended at 67 FR 6182, Feb. 11, 2002; 67 FR 13224, Mar. 21, 2002; 67 FR 41852, June 20, 2002; 67 FR 71111, Nov. 29, 2002; 69 FR 17957, Apr. 6, 2004; 70 FR 31372, June 1, 2005; 71 FR 69046, Nov. 29, 2006; 73 FR 25420, May 6, 2008; 75 FR 62932, Oct. 13, 2010; 80 FR 38823, July 7, 2015]