The next time you go up on the roof of a building to do some work, take a good look around. Whether you are tarring the roof, painting the elevator shaft, washing the windows, maintaining the HVAC or anything else that might keep you there for some time, do yourself a favor and see if there are any antennas nearby. I’m not referring to those old-time aerials that help improve TV reception; they collect radiation. I am talking about antennas that send out signals, that is, transmit radiation. Active antennas may be beaming radiation right at you, and you’ll probably never know it—even if you were to get sick later on.
‘Huge’ number of active antennas The news regularly features stories about the latest cell phone health scares, with headlines like: “Do cell phones cause brain tumors?” or, “Is living or going to school near a cell tower dangerous?” No one has the answer to these questions, and no one will for a long time. But we do already know that it is not a good idea to work right next to a transmitting antenna.
A cell phone puts out at most a couple of watts of radiofrequency/microwave radiation—often called “RF”—usually much less. A rooftop cell phone base station, on the other hand, can transmit a hundred times more energy. And if more than one company has antennas on that same roof, the radiation levels could be much higher. Many other types of transmitters may be there too: fire and police networks, terrestrial and satellite radio, TV and pagers, among others. Some of these can be very powerful, radiating thousands of watts. Not all rooftops have transmitters. But the number of active antennas is huge. There are about a quarter of a million cell sites alone in the U.S., according to CTIA—The Wireless Association, the cell phone trade group. Many of these are stand-alone towers; most of the rest are on the top of buildings. For many owners, the roof is a major profit center. If a building is in a desirable location, the rent collected from the antennas can exceed that paid on the commercial and residential leases. Unlike some tenants, the antennas, once installed, are usually hassle free!
“I tell workers to look around and not to be oblivious to their surroundings,” says Richard Strickland of RF Safety Solutions, a consulting and training firm based on Long Island. Strickland points out that it is very rare for any of these transmitters to be turned off when someone is working nearby. That’s even true for high-power radio and TV stations that broadcast tens of thousands of watts of RF radiation.
OSHA has never taken a strong interest in RF health risks. The only standard on its books was written back in 1966, years before OSHA was established. It requires RF occupational exposures to be less than 10 mW/cm2 (10 milli-Watts per square centimeter). Over the last 40 years, the standard has been updated many times by the groups that developed it, but never by OSHA. You can be sure that a standard is out of date when the military and industry act on their own to make it more stringent. Today, their limit is about 50 times stricter than OSHA’s 1966 10 mW/cm2 standard.
One important technical detail: Most exposure standards specify separate limits for workers and the general public—with a lower limit for the public to allow for the greater vulnerability of the young, the old and the sick. The updated U.S. RF standard, developed by a committee of the Institute of Electrical and Electronics Engineers (IEEE), works differently: It makes a distinction between “voluntary” and “involuntary” exposures. Voluntary exposures apply to those—such as cell phone technicians, who, it is assumed, know they will likely be exposed to RF radiation. Involuntary exposure limits are five to ten times stricter than the voluntary limits to protect those who know little or nothing about radiation, for instance, a roofer working near a cell phone antenna.
OSHA standard out of date
Not only is OSHA’s 10 mW/cm2 standard out of date, but for many years, beginning in the early 1980s, the agency could not or would not enforce it. The trouble started with the fact that the RF standard had originally been adopted as a voluntary—or “should”—standard and OSHA rules dictated that its inspectors could not issue a citation for exceeding a voluntary standard. The agency had a second option: Enforcement under the OSHAct’s general duty clause, which requires all employers to provide workers with a safe environment, free from recognized hazards. Then the Occupational Safety and Health Review Commission (OSHRC), an independent Federal agency which decides contests of citations or penalties resulting from OSHA inspections, and the courts decided that the general duty clause could not be invoked if there was an applicable voluntary standard in the rulebook.
Radiation beamed from active antennas
In 1984, OSHA went ahead and deleted many of its “should” standards, but, at the last minute, a secret decision was made to keep the voluntary RF/microwave limit. This guaranteed that 10 mW/cm2 standard could not be enforced.
Microwave News took OSHA to federal court in an effort to force it to reveal the reasoning behind this decision. OSHA was defended by the U.S. Attorney for the Southern District of New York, who at the time was Rudy Giuliani. The court ruled in favor of OSHA: the documents were deemed to be privileged and have never been released. Twenty-five years later, we still don’t know who put in the fix.
OSHA "ill-equipped" to deal with issue
Larry McGowan in OSHA’s enforcement office in Washington says things are different today. “If OSHA found an RF hazard, OSHA could enforce a violation under the general duty clause,” he said in a recent interview. Maybe so, but OSHA may not have the manpower and expertise to do so.
“At the present time, OSHA is illequipped to deal with the real and mounting concerns associated with RF radiation,” according to Dave LeGrande, Director of Occupational Safety and Health at the Communications Workers of America (CWA).
If OSHA were to enforce RF exposures, the agency would be more likely to do so for those workers who work on antennas rather than the “involuntary” exposures of those who are exposed accidentally. After all, unless the exposures are very high, odds are that a worker will never know he or she got zapped.
In other words, you are on your own. So, be smart, take a close look around a rooftop you may be working on. If you see a yellow and black radiation warning sign or anything else that looks suspicious, ask what it is. If it turns out to be a transmitting antenna, keep your distance.
Radiation beamed from cell phone base stations
Source: Newsletter of the New York Committee for Occupational Safety and Health