RF exposure guidelines

This month's column might be called “Avoiding the toasty-critter syndrome” or “How to fight fear and superstition.” Either of these would be equally appropriate for those unfortunate enough to have to defend their existing or proposed RF facilities in a public forum.


Several government agencies provide guidelines that facilities should use to limit people’s exposure to non-ionizing radiation.

If your proposed station modification requires the approval of a zoning board, zoning board of appeals or any similar group, the question of exposure to non-ionizing radiation is bound to come up. You need to accept the fact that some well-meaning members of the community are honestly and sincerely concerned about the health and safety of themselves and others. Such people deserve your attention and a full explanation of the possible effects of your proposed facilities. There are also those who aren't worried; they realize that you aren't going to turn them into toast. But, inevitably, you will have some kooks who arrive with a 1952 article from Popular Mechanics that they claim holds the definitive word on the matter.

Be informed

Prepare for these meetings by making an immediate and concerted effort to inform yourself of the applicable regulations. Start with our old friend, the Rules and Regulations of the FCC. Section 1.1310 is a brief but meaningful little paragraph that refers you to OST/OET Bulletin Number 65, “Evaluating Compliance with FCC-Specified Guidelines for Human Exposure to Radio Frequency Radiation.” You will also find charts of the basic limits for and definitions of the terms “occupational/controlled exposures” and “general population/uncontrolled exposure.”

Exposure levels

Essentially, there are two levels of exposure about which you need to be concerned: one for people who work at commercial RF transmission sites, and one for the general public. The occupational/controlled level applies in areas where all personnel are aware of the hazard and the exposure is transient and carefully controlled. The general population is protected to a greater degree because they may not be aware that the exposure is occurring. Such exposure might occur where a roof-mounted transmitting antenna exposes people in an adjacent building or people simply walking by the site to RF radiation without their knowledge. The guidelines call for exposing the general population to a level of radiation no more than one fifth that allowed for occupational areas.

The exposures in the rules or contained in the standards are for whole-body exposure averaged over a finite period. For controlled areas, the limit is six minutes; for uncontrolled areas, its 30 minutes. The standards are hard to apply to very localized exposures, as in the case of the state trooper who sued over claimed damage from his radar gun. He had a habit of leaving the device on and placing it in his lap until ready to take a reading — probably setting a new standard for stupidity. You should take reasonable precautions to protect yourself.

There is a wealth of material available to help you prepare to argue your case. Go to good old www.fcc.gov (it should already be on your “favorites” list) and then go to “Engineering and Technology.”

Educating the layman

The first big challenge is to make sure you inform and educate the public officials involved in the hearing. The general public goes into a semi-comatose state whenever they hear the word “radiation.” They really aren't sure what it means, but they automatically assume that “non-ionizing” means that they will be sterilized, vaporized, atomized and generally cooked by any exposure. If you're lucky, the officials whom you must convince are a bit more educated than that — but don't take a chance. The commission prints a document titled “A Local Government Official's Guide to Transmitting Antenna RF Emission Safety: Rules, Procedures, and Practical Guidance.” Download that publication and make sure you distribute it to every member of the board(s) you face, along with a copy of OET Bulletin 56, “Questions and Answers about Biological Effects and Potential Hazards of Radiofrequency Electromagnetic Fields.” (Notice that the government really isn't big on short, catchy titles.)

FAQs

Finally, those who plead your cause should read the list of frequently asked questions on the Web site with the OET bulletin. That section discusses some of the other agencies that are involved with non-ionizing radiation problems, such as OSHA, NIOSH, Department of Defense, etc., and gives Web pages so that you can review their publications on the subject. The big point here is to be educated concerning non-ionizing radiation and its effects. Even if you fully prepare yourself, it will be difficult to convince some members of the public that they are out of harm's way. You don't have a chance if you aren't prepared.

Modified regulations

The commission has recently proposed a rule that will modify the non-ionizing protection requirements of the Rules and Regulations. Docket No. 03-137 proposes changes to several definitions as well as to the way some radiations are calculated or excluded from calculation. Primarily, these changes affect only the wireless-communications crowd. The existing rules tend to exclude transmitters based on the antenna height above ground. That is being changed to more accurately reflect the distance to the observer, regardless of height. You should review those changes. They might apply to your station's remote-pickup facilities, especially those transmitters and antennas that may be at fixed locations.

In summary, prepare yourself before meeting the public at hearings or attempting to argue your case before public officials. Plenty of good information is available, including OET 56 and 65 (confusing, isn't it), sets of questions and answers, and an excellent guide for public officials.

One problem you might encounter is the desire of local governmental groups to enact their own regulations concerning non-ionizing radiation. Now, that is a rather ticklish area. The Telecommunications Act of 1996 clearly outlaws any regulation of wireless facilities based on the environmental effects of RF emissions. On the other hand, the act doesn't treat broadcast radiation the same way. Maybe broadcasters just don't have as much clout as the wireless folks. But then we knew that, didn't we?

Don Markley is president of D.L. Markley and Associates, Peoria, IL.

Send questions and comments to:don_markley@primediabusiness.com

Home | Back to the top | Write us