Sources & emitters

Pole-mounted nodes radiate roughly 10 W EIRP at street level, putting a residence 10 m away at about 8,000 µW/m² on the main beam — far below regulatory limits but often above precautionary building-biology bands.

radiofrequency · Mid band (1.7–2.6 GHz), C-band (3.3–4.2 GHz), mmWave (24–39 GHz)

Live conductors in walls and in lamp flex create a power-frequency electric field that couples to the body whether or not any current flows; building biology grades below 1 V/m with ground reference as 'no anomaly'.

elf electric · Power frequency and harmonics

Class 2 Bluetooth transmits about 2.5 mW — roughly 1/80th of a phone's cellular uplink maximum — but does so a centimetre from the head, so the relevant metric is again SAR rather than power density.

radiofrequency · 2.4 GHz ISM

The highest hand-held power-frequency fields measured in a household set: circular saws reached 1,000 mG (100 µT) at 15 cm and 300 mG (30 µT) at 30 cm, with drills roughly five times lower.

elf magnetic · Power frequency

Older DECT bases transmit a pulsed beacon 100 times per second whether or not a call is in progress; at 250 mW peak that is about 20,000 µW/m² at 1 m.

radiofrequency · DECT 1880–1900 MHz (EU), DECT 6.0 1920–1930 MHz (US)

Phase-cutting dimmers chop the mains waveform and inject harmonics from a few kilohertz up to about 1 MHz onto the building wiring — the classic source of what practitioners call dirty electricity.

dirty electricity · Harmonics 2 kHz–1 MHz

A resistive heating element in direct body contact for eight hours: among the highest whole-night ELF magnetic exposures in a home unless the element is low-field wound or switched off before sleep.

elf magnetic · Power frequency

Small kitchen motors used at arm's length: can openers were the strongest household appliance measured, at 500–1,500 mG (50–150 µT) at 15 cm and 40–300 mG (4–30 µT) at 30 cm, for a few seconds' use.

elf magnetic · Power frequency

EV cabins contain low-frequency magnetic fields from battery cables, traction motor and inverter, strongest in the footwell and over the pack, with a separate profile during fast charging.

elf magnetic · DC and traction ripple, Inverter switching harmonics

The highest-current point in a building: readings in the tens of milligauss are normal within a metre, falling to background within two to three metres.

elf magnetic · Power frequency and harmonics

Ballast-driven tubes measured 20–100 mG (2–10 µT) at 15 cm, falling to at most 30 mG (3 µT) at 30 cm — relevant because the fitting is often directly above a desk or bed rather than at arm's length.

elf magnetic · Power frequency, Electronic ballast switching

Broadcast sites radiate tens to hundreds of kilowatts ERP — thousands of times a cell sector — but from tall masts in the 30–300 MHz band where the FCC's public limit is at its most restrictive.

radiofrequency · FM broadcast (88–108 MHz), VHF/UHF television

Motor appliances held against the head: among the strongest ELF magnetic fields in a home at the point of use — up to 700 mG (70 µT) at 15 cm across the models measured — but used for minutes a day, and down to at most 70 mG (7 µT) by 30 cm.

elf magnetic · Power frequency

Fields directly beneath a loaded transmission line reach tens of milligauss and fall off roughly with distance for a balanced three-phase circuit, reaching background at 30–60 m for typical loadings.

elf magnetic · Power frequency

Away from appliances, homes typically sit below a few milligauss; the WHO's epidemiological association with childhood leukaemia begins at a daily average of 3–4 mG (0.3–0.4 µT).

elf magnetic · Power frequency

Induction hobs work by driving a 20–100 kHz coil, producing intermediate-frequency magnetic fields that are strong at the hob edge and fall off steeply — and that most consumer gaussmeters cannot measure because their bandwidth stops at 2 kHz.

elf magnetic · Intermediate frequency (20–100 kHz)

The switch-mode driver inside a cheap LED lamp can put measurable high-frequency harmonics on the circuit and produce visible flicker; well-filtered drivers do neither.

dirty electricity · Driver switching harmonics

Sector antennas radiate on the order of 1000 W EIRP per sector on the main beam, which is aimed above and away from the tower base — ground-level exposure directly beneath a tower is usually lower than at a few hundred metres away.

radiofrequency · Low band (600–900 MHz), Mid band (1.7–2.6 GHz), C-band 5G (3.3–4.2 GHz)

The only consumer appliance with its own federal leakage standard: 5 mW/cm² at 5 cm from the surface over the product's lifetime, which is 50,000,000 µW/m² — high compared with any communications source.

radiofrequency · 2.45 GHz ISM

A local transformer produces a strong but rapidly decaying magnetic field: often tens of milligauss at a metre, at or near background by five metres.

elf magnetic · Power frequency and harmonics

A phased-array user terminal transmits a narrow beam skyward in Ku band; exposure beside the unit is dominated by sidelobes, and manufacturers specify a keep-out distance in front of the panel.

radiofrequency · Ku-band uplink (14.0–14.5 GHz)

Mesh smart meters transmit in short bursts at up to 1 W EIRP in the 900 MHz band, so peak readings at 1 m are high while time-averaged exposure is low because the duty cycle is well under 1%.

radiofrequency · 902–928 MHz ISM (FHSS)

Handsets transmit up to about 200 mW (23 dBm) on cellular uplink and are used against the head, so exposure is governed by SAR — 1.6 W/kg over 1 g in the U.S., 2 W/kg over 10 g under ICNIRP — not by power density.

radiofrequency · Cellular uplink (700 MHz–3.8 GHz), Wi-Fi / Bluetooth

String inverters and panel-level optimisers switch at kilohertz to tens of kilohertz and are wired into the building's supply, so they can raise both magnetic fields near the DC and AC runs and conducted harmonics throughout the house.

dirty electricity · Power frequency, Switching harmonics

A high-current motor at floor level and at arm's length: 100–700 mG (10–70 µT) at 15 cm and 20–200 mG (2–20 µT) at 30 cm, with no unit in the measured set falling to background at 30 cm.

elf magnetic · Power frequency

A consumer access point radiating roughly 100 mW EIRP per band, giving about 8,000 µW/m² at 1 m and 80 µW/m² at 10 m in free space.

radiofrequency · 2.4 GHz ISM, 5 GHz U-NII, 6 GHz U-NII (Wi-Fi 6E/7)

Continuously streaming 100 mW transmitters, usually mounted at head height near doors and windows, giving about 8,000 µW/m² at 1 m.

radiofrequency · 2.4 GHz ISM, 5 GHz U-NII

A 2.4 GHz video monitor placed a metre from a cot is a continuously transmitting source at close range — roughly 8,000 µW/m² at 1 m for a 100 mW unit.

radiofrequency · 2.4 GHz ISM, DECT / FHSS audio