1.4.3 Managing Exposure

Most members of the general public encounter only relatively low levels of RF exposure arising from everyday communications systems and consumer devices. Some occupations, however, involve working much closer to high-power RF transmitters or industrial RF equipment.

Examples include personnel maintaining broadcasting transmitters, communications towers, radar installations, satellite earth stations, industrial heating equipment, MRI facilities, and military communications systems. These environments may produce RF field strengths significantly higher than those normally encountered by the general public and therefore require appropriate engineering controls, administrative procedures, and RF safety management.

Understanding the nature of the RF source is an essential part of any RF safety assessment. Different systems operate over different frequency ranges, produce different field distributions, employ different transmission characteristics, and present different exposure scenarios. Consequently, the methods used to assess RF exposure and the applicable exposure limits depend not only on the measured field strength but also on the characteristics of the RF source itself.

We discuss the difference between occupational exposure and general-public exposure in Chapter 7, and we investigate appropriate management practices in Chapter 10.