You may have read about a recent change to the FCC regulations governing RF Exposure standards for amateur radio stations. The new rules went into effect on May 3, 2021. While the change does not modify existing RF Exposure (RFE) limits, it does now require that ALL amateur radio licensees evaluate their stations for RFE.
What does this mean for me?
Operators of existing amateur stations have two years to complete an RFE evaluation. However, operators of all new stations or of any existing stations that are modified in a way that’s likely to change their RFE profile — such as different antenna or placement or greater power — will need to conduct an evaluation by the date of activation or change. This means that every station you operate from a legal limit HF station with a beam to a personal Pi-Star or AllStarLink hotspot will have to be evaluated for RFE. Some experts have advised that one should also retain evidence of those evaluations.
Will this change really affect me?
While there is little risk that your low-power HTs and hotspots will will present results that require mitigation of RFE, you might be surprised to find that your 25-50-watt mobile 2-meter radio with a common 6dBi mobile whip antenna will radiate RF in excess of the Maximum Permissible Exposure (MPE) up to to 10-15 feet from the antenna! So it might be a good idea to refresh your knowledge about RFE and be sure that you understand your responsibilities as a licensee.
What can I do to be sure I am in compliance?
The easiest thing to do is to evaluate your station using an online RF exposure calculator. The tool at this link makes the process relatively straightforward. You can simply print the results from the web calculator as evidence of your evaluation. If your station exceeds the MPE for the frequencies you are operating on, you might need to reduce power or relocate your antenna to mitigate the risk of exposure.
Where can I learn more?
There have been a number of online threads and YouTube videos addressing this issue. Many have veered deep into technical discussions with some YouTube videos rambling on for hours on the subject. That is certainly more time than most hams will want to dedicate to regulatory compliance. The most succinct and organized video primer on the subject that I have found is the YouTube video “New FCC RF safety rules for ham radio” from Ria, N2RJ. She has organized the information into chapters with timestamp links. These can be found in the “SHOW MORE” link of her YouTube video description.
If you are looking to take a deep dive into RF Exposure, the ARRL has a page with additional resources including a free PDF of the book “RF Exposure and You.” Just consider that some of the information in older resources may mention an RFE evaluation exemption for low-power amateur stations. While the RFE limits have not changed, the new FCC regulations eliminated this exemption. Now all operators must perform an RFE evaluation for all transmitters regardless of output power*.
Final thoughts …
As K6TZ Trustee, it is my responsibility to ensure that all stations operating under the Club’s callsign are in compliance with FCC regulations. We will be performing RFE evaluations at all of the Club’s existing installations in the near future. I urge you to take a few minutes to learn about RFE and evaluate your own amateur station. You may learn something and enhance the safety of your equipment in the process.
If you are not already, consider subscribing to the SBARC listserver. It is a great place to ask questions discuss issues like this with local hams. Also consider joining the Technical Mentoring and Elmering Net on Thursday evenings at 8pm on the linked SBARC repeaters.
Levi C. Maaia, K6LCM
*There may be some additional relief provided under certain specific exemptions to the RFE regulations. However, such exemptions require additional computations and are beyond the scope of this summary. The quickest and safest way to determine compliance is by performing an evaluation with one of the online RF exposure calculators.