FCC maximum permissible exposure limits
The 47 CFR 1.1310 Table 1 limits, and the detail that gets missed: below 300 MHz the power density column is not actually the limit.
Limits by frequency range
| Frequency | Controlled (mW/cm²) | Uncontrolled (mW/cm²) | Field limits in the rule |
|---|---|---|---|
| 0.3 – 1.34 MHz | 100.00 | 100.00 | E 614.0 V/m, H 1.630 A/m |
| 1.34 – 3 MHz | 100.00 | 45.00 | E 614.0 V/m, H 1.630 A/m |
| 3 – 30 MHz | 4.46 | 0.893 | E 129.7 V/m, H 0.344 A/m |
| 30 – 300 MHz | 1.00 | 0.200 | E 61.4 V/m, H 0.163 A/m |
| 300 – 1500 MHz | 1.49 | 0.297 | — |
| 1.5 – 100 GHz | 5.00 | 1.00 | — |
Averaging time is 6 minutes for occupational / controlled exposure and 30 minutes for general population / uncontrolled.
Below 300 MHz the power density is only an equivalent
In the ranges above, the rule marks the power density column as plane-wave equivalent and gives electric and magnetic field strength as the limits that actually bind. That matters because close to an HF antenna you do not have a plane wave. A power density estimate at a few metres on 80 m should be treated as indicative and backed up by the field strength columns or by measurement.
Limits at amateur band frequencies
| Band | Frequency | Controlled | Uncontrolled |
|---|---|---|---|
| 160 m | 1.9 MHz | 100.00 | 49.86 |
| 80 m | 3.8 MHz | 62.33 | 12.47 |
| 40 m | 7.15 MHz | 17.60 | 3.52 |
| 20 m | 14.2 MHz | 4.46 | 0.893 |
| 15 m | 21.3 MHz | 1.98 | 0.397 |
| 10 m | 28.4 MHz | 1.12 | 0.223 |
| 6 m | 50.15 MHz | 1.00 | 0.200 |
| 2 m | 146 MHz | 1.00 | 0.200 |
| 70 cm | 446 MHz | 1.49 | 0.297 |
| 23 cm | 1296 MHz | 4.32 | 0.864 |
| 13 cm | 2400 MHz | 5.00 | 1.00 |
| 6 cm | 5760 MHz | 5.00 | 1.00 |
Power density in mW/cm².
One discontinuity in the table
The rule is exactly continuous at every band boundary but one. The uncontrolled limit of 180/f² reaches 100 mW/cm² at f = √1.8 = 1.3416 MHz, but the breakpoint is written as 1.34 MHz, so the limit steps up by 0.25 % there. It is in the published table, not a rounding artefact.
Evaluations are now required
The 2019 rule change removed the service-specific exemptions that let many stations skip an evaluation. In practice that means performing one and keeping the record.
Related tool: RF exposure evaluation, which computes compliance distances and produces a printable station record.