The radiofrequency (RF) part of the electromagnetic spectrum is conventionally defined as extending from 3 kilohertz (kHz) to 300 gigahertz (GHz) and includes a great many applications ranging in power level from very low (e.g. wireless key fobs, Wi‐Fi) to very high (e.g. some broadcast and radar facilities, industrial heaters). While RF energy is nonionizing, in the sense that its photons have insufficient energy to disrupt chemical bonds and form free radicals), exposure to RF energy at high levels can be quite hazardous. The presence of high‐powered RF sources in some occupational settings creates challenges for the industrial hygienist (IH), regarding both exposure assessment and control. This chapter reviews elementary aspects of RF safety, including RF sources in occupational settings with the potential of producing exposures above recommended limits, relevant exposure limits, elements of exposure assessment, and RF protection programs.