Answer to Question #11043 Submitted to "Ask the Experts"

Category: Micro/Radio Waves, Radar & Powerlines — Microwaves and Radiofrequency

The following question was answered by an expert in the appropriate field:

Q

Is it safe for me and my family, which includes a three-year-old, to live 46 meters from a police communications tower?

A

The short answer to the question is yes, it is safe. 

One way to judge safety is to compare the expected radiofrequency (RF) exposure levels in normally accessible locations around a site, such as a police communications tower, with science-based safety limits. The 60-plus year history of the study of potential biological effects associated with exposure to RF energy has led to a large body of scientific literature of peer-reviewed reports and studies. Independent reviews of this literature by expert panels throughout the world conclude that the weight of scientific evidence, including the results of epidemiological studies of individuals exposed to radiowaves and laboratory studies of animals exposed both short-term and throughout their entire lifetimes, has not demonstrated that exposure to RF energy at levels that comply with contemporary science-based safety guidelines, such as those adopted by the Federal Communications Commission (FCC) or recommended by the World Health Organization (WHO), can affect biological systems in a manner that might lead to, or augment, any health effect or interfere with the operation of medical devices such as hearing aids or implanted cardiac pacemakers.

Regarding sites typical of those in question, e.g., tower-mounted antennas used for personal wireless communications and emergency radio services, the maximal levels of RF energy in areas normally accessible to the public have been found to be far below contemporary safety standards and guidelines. There are several reasons why this is so: (1) the systems operate at low power levels (compared with systems used for commercial AM/FM radio and television broadcast) since they are designed to cover a limited area, (2) the RF energy is emitted from the antennas in a fairly narrow angular distribution in the vertical (so-called elevation) plane, i.e., comparatively little energy is directed downward in the vicinity of the antenna support structure, and (3) the height of the antennas above ground and the narrow elevation beam ensures that the energy is propagated above the roofs of nearby homes and offices. Moreover, because of the attenuation of building materials, the levels inside of nearby homes and offices will be lower than outside.

Measurements carried out over the years confirm that the levels of RF energy in normally accessible areas in the vicinity of installations such as tower-mounted antennas used for public-safety radio systems are typically less than 1 percent of the regulatory standards mandated by the FCC via the Telecommunications Act of 1996. Such regulatory standards are science-based and include large factors of safety to address various uncertainties.

A lot is known about the safety of electromagnetic energy at radiofrequencies. What is important is that thanks to the significant amount of research that has been reported in this field over the past six decades, national and international expert panels and health agencies have consistently concluded that exposure to RF energy at levels below FCC regulatory standard and WHO-endorsed safety guidelines is safe to humans, including children. It is important to point out that reliable scientific evidence indicates that biological effects associated with exposure to RF energy are “threshold effects.” This means that adverse effects are only associated with exposures above a specific intensity, well above current FCC regulatory standard and WHO-endorsed exposure guidelines. (This is a completely different phenomenon than that associated with exposure to ionizing radiation such as x rays, etc., where exposure duration is important because even low-level exposure produces effects that accumulate over time.) The threshold exposure levels at which potentially harmful effects of RF energy might occur have been independently established and confirmed many times over. These thresholds, with large built-in margins of safety, are the bases of contemporary safety guidelines and recommendations, such as those supported or developed independently by expert panels and committees worldwide.

In summary, based on a comparison of the levels of exposure to RF energy found in the vicinity of installations such as you describe with contemporary safety limits based on more than 60 years of research, there is no reason to believe that living near the communications tower would be unsafe for you and your family.

Ron C. Petersen

Answer posted on 3 November 2014. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.