RF Exposure Calculations for Emergency Commmunication

I’ve calculated some safe distances for RF exposure in typical emergency communication situations. These are for a 5 W HT (handheld radio) or a 50 W mobile, on 2 m and 70 cm, each with typical antennas. The results may also be useful for other VHF/UHF portable activities, like ARRL Field Day, Summits on the Air, or Jamboree on the Air.

Very short version: The 6-7 foot social distance we’ve learned to keep is safe for a typical fixed or mobile em-comm deployment. This is the distance between any part of the antenna, including the radials, and a member of the general population. 5 W HTs are safe for handheld use.

The FCC introduced new RF exposure rules for amateur radio in 2021. Hams used to have special exemptions, now we need to do RF exposure evaluations for all uses. If your transmitter and antenna are like the setup used for these calculations, you might be able to use these results. If yours are significantly different, this should help you get started.

Rf safety sign

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