The IEEE established two military exposure environments (i.e. restricted and unrestricted) that can be further divided into three zones. Zone 0 applies to unrestricted environments and Zone 1 and Zone 2 apply to restricted environments.3 Appendix A shows IEEE safety exposure limits for Zone 0 and Zone 1.3 Aboard Navy ships, for example, high-power RF-EMF emitters (e.g., antennas below 100 MHz) can induce current through human body when in close proximity.7 The US Navy defined almost all topside of a ship as restricted “controlled” areas whereas RF-EMF radiation risk mitigation, protection, and management are essential for military operations.
Examples of military RF-EMF emitting sources are listed below based on application categories:8
- COMMUNICATIONS: Military Auxiliary Radio System, Combat-net radio, Land Mobile radio, airborne and ground DataLink or terminal, satellite communication terminal, tropospheric scatter system, wireless local area network, or AM and FM broadcast station.
- NAVIGATION: fixed navigation systems such as VHF Omni-Directional radio, Tactical Air Traffic Navigation, or Instrument Landing System; airborne systems such as radar altimeter, doppler radar, or terrain-following radar.
- RADAR: air defense ground-based radar, airport surveillance radar, counter-battery radar, synthetic aperture radar, moving target indicator, height-finding radar, fire control radar, side looking radar, weather radar, or mapping radar.
- ELECTROMAGNETIC COUNTERMEASURES: electronic countermeasures, threat recognition system, counter-Improvised Explosive Device equipment, or radio and radar jammers.
- INDUSTRY/COMMERCIAL: RF welders or heat sealers, RF induction heating, plasma processing, or microwave heaters.
- MEDICAL: MRI, RF diathermy, patient monitors, cauterization electrosurgery, and interstitial microwave hyperthermia.
- DIRECTED ENERGY WEAPONS: the Active Denial System, Vigilant Eagle, the Tactical High-power Operational Responder, and the Counter-electronics High-power microwave Advanced Missile Project.
Historically, RF-EMF overexposures were less common in military environments and most reported cases were below exposure limits (see Clinical Scenarios below).9,10 Over the nine-year period from 2014 to 2022, the U.S. Air Force reported and investigated 126 suspected cases among 38,000 personnel who routinely worked closely with high-power RF-EMF emitters.10 Only one patient had EMF-related injury confirmed by these investigations.10