# Household background magnetic field (50/60 Hz)

> 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).

- Canonical URL: https://emfbase.com/emitters/household-background-magnetic-field
- Collection: Sources & emitters
- Record id: `emitters:household-background-magnetic`
- Status: verified
- Last verified: 2026-08-12
- JSON: https://emfbase.com/api/emitters/household-background-magnetic-field
- Also known as: background EMF, ambient magnetic field

## Key values

- **Category:** elf magnetic
- **Emission bands:** Power frequency
- **Environments:** home
- **Duty cycle:** Continuous, varying with household and grid load; evening peaks are common.

## Field strength by distance

- **1 m:** 0.1–4 mG — Measured range — Range commonly reported in residential surveys away from appliances and service equipment. Values above this usually indicate a specific source: service panel, wiring error, or an external line. [niehs-emf, who-elf]

## Mitigations, most effective first

- **Log for 24 hours rather than spot-reading; use the 95th percentile of night-time values for a bedroom assessment.** — Power-frequency fields track load and vary hour to hour, so spot readings mislead.
- **Walk the perimeter with the meter to find the source before considering any mitigation.** — Elevated background is nearly always one identifiable source, most often the service panel or a net-current wiring fault.

## Measure with

- ELF gaussmeter (power-frequency magnetic field)
- Logging EMF instrument

## Related records

- [WHO/IARC ELF magnetic field association threshold (0.3–0.4 µT)](https://emfbase.com/limits/who-elf-0-3-0-4-microtesla-association): The average daily exposure level above which pooled epidemiological studies report an association with childhood leukaemia, and the basis for the IARC Group 2B classification of ELF magnetic fields.
- [Building Biology SBM-2024 AC magnetic field bands](https://emfbase.com/limits/building-biology-ac-magnetic-bands): Sleeping-area grades at 50/60 Hz: below 0.2 mG no anomaly, 0.2–1 mG weak, 1–5 mG strong, above 5 mG extreme.
- [ELF magnetic field survey](https://emfbase.com/protocols/elf-magnetic-survey): A source-finding walkthrough plus a 24-hour log, because power-frequency magnetic fields track electrical load and a spot reading answers almost nothing.

## Sources

- `niehs-emf` National Institute of Environmental Health Sciences. *Electric and Magnetic Fields*. https://www.niehs.nih.gov/health/topics/agents/emf — government, link checked 2026-08-12
- `who-elf` World Health Organization (2007). *Electromagnetic fields and public health: exposure to extremely low frequency fields*. https://www.who.int/teams/environment-climate-change-and-health/radiation-and-health/non-ionizing/exposure — government, link checked 2026-08-12
- `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.