Part of our Start Here: A New Ham’s Guide to Getting on the Air guide.
A lot of hams still think RF exposure evaluations are something only high power contest stations need to worry about. That has not been true since 2021, and the grace period for catching up ended back in 2023, so if you have never run the numbers on your own station, this is worth ten minutes of your time.
What actually changed
New FCC rules governing RF exposure evaluations went into effect on May 3, 2021. The permitted exposure limits themselves did not change, but the amateur radio specific exemption that had let most stations skip a formal evaluation was removed and replaced with the FCC’s general exemption criteria, which is narrower. A two year transition period followed to give existing stations time to check and, if needed, adjust their setups. That transition period ended May 3, 2023, and every US amateur station has been expected to be evaluated and in compliance since then, with a fresh evaluation required any time you make a change that could affect exposure, like a new antenna, more power, or a different mounting height.
Are you actually exempt
Some stations remain categorically excluded from needing a routine evaluation, generally based on power level and frequency, with the specific thresholds laid out in the FCC’s OET Bulletin 65 Supplement B. Handheld and mobile transmitters used in the way they are normally operated are generally excluded outright. But categorical exclusion does not mean you are exempt from the actual exposure limits, it only means the FCC does not require you to formally document an evaluation. Higher power HF stations, especially with antennas mounted close to living or working spaces, are the setups most likely to actually need the calculation done and kept on file.
How to actually do the evaluation
- Use the ARRL’s free RF Exposure Calculator, which walks through your power, frequency, antenna type, and gain, and tells you whether you are exempt and, if not, what minimum distance keeps you within the allowed limits.
- Evaluate against the occupational/controlled limits for yourself and members of your own household, since those limits are more permissive, provided everyone in the household has been informed about RF exposure. Anyone outside your household, including neighbors, must be evaluated against the stricter general population limits.
- Keep a record of your evaluation. It does not need to be filed with the FCC, but you should be able to produce it if your compliance is ever questioned.
- Re-run the evaluation any time something changes: a new antenna, an amplifier, a different mounting location, or a significant increase in the power you actually run.
Why it is worth taking seriously
Beyond simply being the rule, an RF exposure evaluation gives you genuine peace of mind about your own setup, and it gives you a straightforward, documented answer if a neighbor or family member ever raises a concern. It takes far less time than most people expect, usually just plugging numbers into the ARRL calculator, and it is one of those compliance tasks that is easy to keep putting off until it is not.