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Who must meet the FCC's new RF exposure guidelines?

All amateurs are required to comply with the new Maximum Permissible Exposure (MPE) limits. The MPE Calculator was developed to perform the calculations and prepare the complete station evaluation necessary to document compliance with the MPE limits.


Effective January 1, 1998, amateurs whose stations exceed the following power thresholds must perform the required station evaluation:













Repeater Stations (all bands): an evaluation is required for building-mounted antennas where power exceeds 500 watts ERP, and for non-building-mounted antennas if height above ground to the lowest point of the antenna is less than 10 meters and the power exceeds 500 watts ERP.


Stations using indoor or attic antennas should be considered for evaluation (even if not exceeding the power thresholds) due to the unusually close proximity of such antennas to individuals - in both controlled and uncontrolled categories.


Mobile and portable (hand held) transmitters are categorically excluded from the routine evaluation requirement. However, they are still required to comply with the MPE limits. In particular, mobile stations using high power should be considered for evaluation.


Even if the regulations do not require an evaluation, the results of such an evaluation would demonstrate to the amateur and his or her neighbors that the station's operation is well within the guidelines and is not a cause for concern.


Regardless of categorical exemption or power threshold exemption, the FCC's rules require compliance with the MPE limits. In the case of unusual circumstances, the FCC may ask that an evaluation be performed on any transmitter regulated by the FCC.


160-40 meters

500 watts

6 meters

50 watts

30 meters

425 watts

1.25 meters

50 watts

20 meters

225 watts

70 cm

70 watts

17 meters

125 watts

33 cm

150 watts

15 meters

100 watts

23 cm

200 watts

12 meters

75 watts

13 cm

250 watts

10 meters

50 watts


250 watts