# 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.

- Canonical URL: https://emfbase.com/quantities/body-voltage
- Collection: Quantities & units
- Record id: `quantities:body-voltage`
- Status: verified
- Last verified: 2026-08-12
- JSON: https://emfbase.com/api/quantities/body-voltage
- Also known as: body voltage measurement, mV body voltage

## Key values

- **Symbol:** U
- **SI unit:** V
- **Units in use:** V, mV

## What it measures

Capacitive coupling between household wiring and the body. It is a proxy for the local AC electric field and depends strongly on grounding method, so readings are only comparable when the protocol is identical.

## Units

Multiplier to the SI unit (V).

- **V (volt)** — 1 V = 1 V
- **mV (millivolt)** — 1 mV = 0.001 V

## 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.

## 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.