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Hams now have basic guidelines and tools to evaluate their stations for compliance with the FCC’s RF exposure guidelines that go into effect January 1, 1998. On November 18, the FCC’s Office of Engineering and Technology issued the long-anticipated Amateur Radio Supplement B to OET Bulletin 65 (http://www.fcc.gov/oet/info/documents/bulletins/#65). The FCC worked closely with the Amateur Radio community in developing the new supplement. Several ARRL Headquarters staff members and Technical Advisors were involved in reviewing preliminary drafts of the supplement. ARRL Lab Supervisor Ed Hare, W1RFI, has been the League’s point man for RF safety and exposure issues.
Supplement B, subtitled "Additional Information for Amateur Radio Stations," contains detailed information specific to ham radio stations. It is designed to be used in conjunction with the FCC’s OET Bulletin 65 (Version 97-01) (http://www.fcc.gov/oet/info/documents/bulletins/#65), Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields. The revised Bulletin 65 was issued earlier this year. Supplement B covers definitions of RF radiation and discusses the FCC exposure guidelines and their applications, methods of predicting human exposure, estimating compliance distances, and controlling exposure to RF fields. The supplement runs approximately 60 pages. Among its noteworthy highlights are numerous easy-to-use tables based on various frequencies, power levels and antenna configurations to help hams determine whether their stations comply with the FCC’s published RF exposure guidelines. Most of the tables show compliance distance, the distance that an antenna needs to be located from areas of exposure to be in compliance. The January, 1998 issue of QST features an article, "FCC RF-Exposure Regulations -- the Station Evaluation," by Ed Hare, W1RFI, that describes Supplement B and tells hams how to use it to complete their station evalautions.
OET Bulletin 65 and the new Supplement B can all be viewed and downloaded from the FCC's OET World Wide Web Site: http://www.fcc.gov/oet/info/documents/bulletins/#65. Copies can also be purchased from the Commission's duplicating/research contractor: International Transcription Service, Inc., 1231 20th Street, N.W., Washington, D.C. 20036; Telephone: (202) 857-3800, FAX: (202) 857-3805.
This page was created as an information resource on the many questions being raised by hams about the rules change regarding RF exposure that the FCC announced on August 1, 1996. Details can be found in the listing of resources that follows this overview. These regulations control the amount of RF exposure to people that can result from your station's operation. They also require that certain types of stations be evaluated to determine if they are in compliance with the rules. The FCC has also required that five questions on the general topic of RF environmental safety practices be added to Novice, Technician and General Class examinations.
The new rules were effective when the original Report and Order was released on August 1, 1996, with a transition period for stations to come into compliance set to January 1, 1997, however the FCC granted a request by the ARRL to extend the transition date until January 1, 1998. This was further changed by the Second MO&O, leaving the January 1, 1998 date in effect for new applications, or applications for renewal or station modification requiring an FCC Form 610 application, but adding an additional date certain of September 1, 2000 for existing stations that need not file an application with the FCC, including amateur, to come into full compliance.
Regulations on RF exposure have been on the books since the mid 1980s. These regulations were based on the 1982 IEEE/ANSI C95.1 RF-exposure standards. The regulations set limits on the maximum permissible exposure (MPE) permitted from operation of transmitters in all radio services, including the Amateur Radio Service and required some radio services to conduct station evaluations to ensure that they were in compliance. Amateurs were categorically exempt from the requirement to evaluate their stations because the relatively low power and typical operating duty cycles used by hams made it unlikely that the MPE levels would be exceeded.
The new regulations set new MPE limits. Some of the categorical exemptions for the Amateur Radio Service have been eliminated. As they always have, hams are required to meet the limits for MPE. As first announced, the rules set a threshold of 50 watts PEP to trigger the need for amateurs to conduct a "routine station evaluation" of their station's operation. The ARRL petitioned the FCC to increase this limit, scaled to match the way the regulations vary with frequency. The Second MO&O announced a rules change that increased the exempted power level on most amateur bands. Amateur stations using less than the limits shown in the table in the regulations, or mobile or portable stations using push-to-talk do not need to be evaluated. They still must meet the exposure levels in the rules, but by virtue of their relatively low power, they are presumed to be in compliance.
These regulations are not a major burden on the Amateur Radio Service. Most hams are already in compliance with the MPE requirements. Some hams will need to conduct a simple evaluation, with most using the lookup tables being prepared by the FCC to determine if their antennas are far enough away from areas of exposure for the mode and power they are using. The FCC has prepared a bulletin, OET Bulletin 65, "Evaluating Compliance with FCC-Specified Guidelines for Human Exposure to Radio Frequency Radiation," that contains some of the information Amateur Radio operators will need to complete this evaluation.
Bulletin 65 was released on August 25, 1997. A separate supplement for the Amateur Radio Service was released on November 18, 1997. Most hams will use the simple tables that are going to be part of the supplement, but they can also use other methods of evaluation, such as computer modeling or actual field-strength measurements.
The ARRL has filed a number of Petitions for Partial Reconsideration. To date, we have been successful at having the original transition-period implementation date extended from January 1, 1997 to January 1, 1998, to give hams enough time to meet the requirements of the rules. The FCC is also permitting the question pools to be updated in their normal cycle. ARRL worked with the Question Pool Committee (QPC) to release revised question pools for the Novice and Technician Class question pools on schedule for December 1, 1996. The ARRL was also successful at persuading the FCC to increase the power levels for categorical exemptions for some amateur operation.
To get a full understanding of the rules as they now stand, you will need to look in several places. Here is a list of various recently published ARRL information on the topic.
ARRL Periodicals Index Search - This database contains the QST index from 1915 to the present and the QEX index from 1981 to the present. For QST issues from 1970 to the present, and some selected articles back to 1950, identifying keywords have been added to the database. By entering keywords (ANTENNA) or combinations of keywords (CONSTRUCTION ANTENNA VERTICAL HF) into the Title words: field, you may create dynamic bibliographies.
Technical article KEYWORD list. Hints for more successful searching
Suggested keywords for more articles like the ones on this page are: RF EXPOSURE
