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Introduction

Amateur Radio is basically a safe activity. In recent years, however, there has been considerable discussion and concern about the possible hazards of electromagnetic radiation, including both RF energy and power-frequency (50-60 Hz) electromagnetic fields.

In 1996, the FCC announced new rules governing exposure to transmitted radio frequency signals. The new rules set new limits on the amount of RF energy people can be exposed to. They also require that some stations be evaluated to see if they are in compliance with the rules.

Here we present some QST and Web articles and Links to help clarify what hazards there may be and how to deal with them.

The article, "RF Safety at Field Day" is an example of what can be done to comply in a very public and uncontrolled environment. See also the list of other articles about RF safety.

Additional resources

• The ARRL Handbook for Radio Amateurs
• RF Exposure and You
• RF Exposure Regulations News TIS Page
• QST Magazine

Articles

Note: Some of the following articles are in Adobe Portable Document Format (PDF) files. To view and print these files, you'll need a copy of Adobe's Acrobat Reader program. (Version 3.0 or later required). More information here.

• "The FCC's New RF-Exposure Regulations," by Ed Hare, W1RFI
  QST, January 1997, pp 47-50
  This article described the new rules, and the highlights of ARRL's petitions for change.
• "What's New About the FCC's New RF-Exposure Regulations," by Ed Hare, W1RFI
  QST, October 1997, pp 51-52
  ARRL tells hams about the rules changes and the availability of "Bulletin 65"
• "FCC RF-Exposure Regulations -- the Station Evaluation," by Ed Hare, W1RFI
  QST, January 1998, pp 50-55.
  This article describes Supplement B and tells hams how to use it to complete their station evaluations.
• RF Safety at Field Day (330,235 bytes, PDF file)
  QST June 1999, pp. 48-51
  A case study of Field Day with NSRC in a public park
  
• RF Exposure Regulations News
  FCC Issues RF Safety Supplement B to OET Bulletin 65
• RF Exposure Station Evaluation and Exemption Worksheets
  RF Exposure and You, pp. 1.2-1.5
• Dayton 2002 RF Safety Forum (588,056 bytes, PDF File)

Note:

Contact information for suppliers mentioned in the above articles should first be confirmed using TIS Address Database Search.

N9GL's RF Safety Column

FCC RF Exposure Regulations Reports and Such

• FCC RF Exposure Regulations News Release (Report and Order 96-326), August 1, 1996.
  This is the FCC announcement for the new rules.
• FCC extends compliance transition period (FCC report).
  In response to a petition from the ARRL, the FCC extended the transition period and agreed that the required questions for the Amateur Radio examinations for some classes of license could be updated in their normal cycles.
• FCC RF Exposure Regulations First Memorandum Opinion and Order 96-487, December 23, 1996
  The FCC responds to several petitions for reconsideration and extends the transition period for the Amateur Radio and commercial services.
• FCC RF Exposure Regulations Second Memorandum Order and Opinion 97-303.
  The FCC responds to all the Petitions for Partial Reconsideration and announces new changes to the rule (FCC Second Memorandum and Order) and makes OET "Bulletin 65" available for download.
• OET Bulletin 65
  Evaluating Compliance with FCC-Specified Guidelines for Human Exposure to Radio Frequency Radiation."

RF Exposure General Information

• FCC RF Exposure Regulations overview
• FCC Frequently Asked RF Exposure Questions
• FCC Radio Frequency Safety
  Cellular Telephone Specific Absorption Rate (SAR)
• FCC Q & A about Biological Effects and Potential Hazards of Radiofrequency Electromagnetic Fields
• FCC Office of Engineering and Technology (OET) home page
• OET Report: Measurements of Environmental Electromagnetic Fields at Amateur Radio Stations

Other General Resources on RF safety

• What about the so-called "long-range cordless telephones"
  ARRL Asks FCC to Investigate Long-Range Cordless Telephone Sales
• RF Safety Information
  RF Safety is a big concern in the Wireless / Electronics Industry. This page is intended to help you understand the basic theory of RF Safety, check your designs for RF Safety, analyze and determine trade-offs for different RF Safety levels, and review existing standards and guidelines
• The ARRL Handbook's RF safety coverage as a Web pageor as an Adobe Portable Document Format file (Requires Adobe Acrobat, 63,260 bytes)
• The RFSAFETY program was written by Wayne Overbeck, N6NB.
• RF Safety Calculator
• IEEE Engineering in Medicine and Biology Society -- Committee on Man and Radiation (COMAR)
• PACEMAKERS
• Cell Phone Facts
  FDA Consumer Information on Wireless Phones

ARRL RF Safety Committee

Some Sensible Guidelines developed by the ARRL RF Safety Committee. Although antennas on towers (well away from people) pose no exposure problem, make certain that the RF radiation is confined to the antennas' radiating elements themselves. Provide a single, good station ground (earth), and eliminate radiation from transmission lines. Use good coaxial cable, not open-wire lines or end-fed antennas that come directly into the transmitter area. No person should ever be near any transmitting antenna while it is in use. This is especially true for mobile or ground-mounted vertical antennas. Avoid transmitting with more than 25 W in a VHF mobile installation unless it is possible to first measure the RF fields inside the vehicle. At the 1-kW level, both HF and VHF directional antennas should be at least 35 ft above inhabited areas. Avoid using indoor and attic-mounted antennas if at all possible. Don't operate high-power amplifiers with the covers removed, especially at VHF/UHF. In the UHF/SHF region, never look into the open end of an activated length of waveguide or point it toward anyone. Never point a high-gain, narrow-bandwidth antenna (a paraboloid, for instance) toward people. Use caution in aiming an EME (moonbounce) array toward the horizon; EME arrays may deliver an effective radiated power of 250,000 W or more. With hand-held transceivers, keep the antenna away from your head and use the lowest power possible to maintain communications. Use a separate microphone and hold the rig as far away from you as possible. Don't work on antennas that have RF power applied. Don't stand or sit close to a power supply or linear amplifier when the ac power is turned on. Stay at least 24 inches away from power transformers, electrical fans and other sources of high-level 60-Hz magnetic fields.