# Bedroom wiring AC electric field

> 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'.

- Canonical URL: https://emfbase.com/emitters/bedroom-wiring-electric-field
- Collection: Sources & emitters
- Record id: `emitters:bedroom-wiring-electric-field`
- Status: verified
- Last verified: 2026-08-12
- JSON: https://emfbase.com/api/emitters/bedroom-wiring-electric-field
- Also known as: body voltage, AC electric field bedroom

## Key values

- **Category:** elf electric
- **Emission bands:** Power frequency and harmonics
- **Environments:** home
- **Duty cycle:** Continuous — the field exists whenever the circuit is energised, even with everything switched off.

## Field strength by distance

- **30 cm — electric field strength:** 1–50 V/m — Measured range — SBM-2024 bands with ground reference: <1 V/m no anomaly, 1–5 weak, 5–50 strong, >50 extreme. Without ground reference the bands are <0.3 / 0.3–1.5 / 1.5–10 / >10 V/m. [sbm-2024]
- **30 cm — body voltage:** 10–1,000 mV — Measured range — SBM-2024 body-voltage bands with ground reference: <10 mV no anomaly, 10–100 weak, 100–1000 strong, >1000 extreme. Readings depend entirely on the grounding method used, so protocol must be identical to compare. [sbm-2024]

## Mitigations, most effective first

- **Unplug bedside lamps and chargers at the socket, not just at the switch.** — Removes the nearest energised conductor, usually the largest single contribution at the pillow.
- **Fit a demand switch (Netzfreischalter) on the bedroom lighting circuit.** — De-energises the circuit when no load is drawing, eliminating the field for the whole night.
- **Use shielded cable or grounded shielding paint on the wall behind the bed head where rewiring is impractical.** — Grounded conductive surfaces block power-frequency electric fields effectively — unlike magnetic fields.

## Measure with

- AC electric field meter
- Body-voltage measurement kit

## Related records

- [Building Biology SBM-2024 AC electric field bands](https://emfbase.com/limits/building-biology-ac-electric-bands): Sleeping-area grades with ground reference: below 1 V/m no anomaly, 1–5 weak, 5–50 strong, above 50 V/m extreme; body voltage below 10 mV is 'no anomaly'.
- [Body-voltage measurement](https://emfbase.com/protocols/body-voltage-survey): The building-biology method for grading a sleeping area's AC electric field: a high-impedance millivoltmeter, a hand electrode, and a documented ground reference.
- [Body voltage](https://emfbase.com/quantities/body-voltage): Millivolts induced on a person by nearby power-frequency electric fields, measured against a ground reference; the metric building biologists use to judge bedroom wiring.

## Sources

- `sbm-2024` Institut für Baubiologie + Nachhaltigkeit (IBN) (2024). *Building Biology Evaluation Guidelines for Sleeping Areas (SBM-2024)*. https://buildingbiology.com/site/downloads/SBM-2024_EVALUATION_GUIDELINES_EN.pdf — ngo, link checked 2026-08-12

Data licence: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Dataset version 2026.08.1. Retrieved from EMFBase, https://emfbase.com.

This record is reference data, not medical or legal advice. Regulatory limits, scientific guidelines and precautionary values are labelled separately and answer different questions.