Distance and exposure estimator
S = EIRP / (4πd²) gives the main-beam free-space upper bound. Real exposure is almost always lower — and this formula is simply invalid within about a wavelength of the antenna, which is where a handset against the head sits.
79,577 µW/m² at 10 m
= 0.0796 W/m² = 5.48 V/m (far-field equivalent)
S = EIRP / (4πd²)
- Main-beam (boresight) value: exposure off the beam axis is lower, often by one to two orders of magnitude
- Free space: no absorption by walls, vegetation or bodies, and no reflection gain
- Far field: invalid closer than roughly one wavelength from the antenna
- Continuous transmission: a duty cycle below 100% reduces time-averaged exposure proportionally
Compared with published values
Regulatory values are enforceable, guidelines are recommendations, and precautionary values are proposed by professional or advocacy bodies and are not law anywhere. A number can sit far below the first and far above the third at the same time.
| Value | Kind | Limit | Estimate as % of it | Free-space distance to reach it |
|---|---|---|---|---|
| FCC occupational MPE, 1.5–100 GHzFCC Maximum Permissible Exposure (47 CFR 1.1310) · occupational · 1500–100,000 MHz | regulatory | 50000000 µW/m² | 0.159% | 0.399 m |
| FCC general population MPE, 1.5–100 GHzFCC Maximum Permissible Exposure (47 CFR 1.1310) · general public · 1500–100,000 MHz | regulatory | 10000000 µW/m² | 0.796% | 0.892 m |
| UK enforceable general-public limit, 2–300 GHzUK Ofcom EMF licence condition · general public · 2–300 GHz | regulatory | 10000000 µW/m² | 0.796% | 0.892 m |
| Australian general-public limit, 2–300 GHzARPANSA RPS S-1 (2021) · general public · 2–300 GHz | regulatory | 10000000 µW/m² | 0.796% | 0.892 m |
| FCC general population MPE, 300–1500 MHzFCC Maximum Permissible Exposure (47 CFR 1.1310) · general public · 300–1500 MHz | regulatory | 2000000 µW/m² | 3.98% | 1.99 m |
| India base-station limit, 2–300 GHzIndia DoT base-station EMF norms (1/10th of ICNIRP) · general public · 2–300 GHz | regulatory | 1000000 µW/m² | 7.96% | 2.82 m |
| China public limit, 30–3000 MHzChina GB 8702-2014 electromagnetic environment control limits · general public · 30–3000 MHz | regulatory | 400000 µW/m² | 19.9% | 4.46 m |
| China public limit, 3–15 GHzChina GB 8702-2014 electromagnetic environment control limits · general public · 3000–15,000 MHz | regulatory | 400000 µW/m² | 19.9% | 4.46 m |
| India base-station limit, 400–2000 MHzIndia DoT base-station EMF norms (1/10th of ICNIRP) · general public · 400–2000 MHz | regulatory | 200000 µW/m² | 39.8% | 6.31 m |
| Russia public limit, 300 MHz–300 GHzRussia SanPiN public RF limits · general public · 0.3–300 GHz | regulatory | 100000 µW/m² | 79.6% | 8.92 m |
| ICNIRP 2020 general public reference level, 2–300 GHzICNIRP 2020 RF guidelines (100 kHz–300 GHz) · general public · 2–300 GHz | guideline | 10000000 µW/m² | 0.796% | 0.892 m |
| Safety Code 6 uncontrolled reference level, 6–15 GHzHealth Canada Safety Code 6 (2015) · general public · 6000–15,000 MHz | guideline | 10000000 µW/m² | 0.796% | 0.892 m |
| ICNIRP 2020 general public reference level, 400 MHz–2 GHzICNIRP 2020 RF guidelines (100 kHz–300 GHz) · general public · 400–2000 MHz | guideline | 2000000 µW/m² | 3.98% | 1.99 m |
| Safety Code 6 uncontrolled reference level, 300–6000 MHzHealth Canada Safety Code 6 (2015) · general public · 300–6000 MHz | guideline | 1290000 µW/m² | 6.17% | 2.48 m |
| Building Biology SBM-2024 RF band: extreme anomalyBuilding Biology SBM-2024 evaluation guidelines · sensitive · per single RF source, peak | precautionary | 1000 µW/m² | 7,958% | 89.2 m |
| EUROPAEM 2016 night-time target value for WLAN and similar pulsed sourcesEUROPAEM EMF Guideline 2016 · sensitive · pulsed digital services | precautionary | 10 µW/m² | 795,775% | 892 m |
JSON: /api/safe-distance