ELF (extremely low frequency)

Definition

Extremely low frequency covers roughly 3–300 Hz and in practice means power-frequency fields from wiring, appliances, transformers and transmission lines. ELF electric and magnetic fields are treated as separate quantities because they are not coupled at these frequencies, and the biological concern addressed by exposure limits is induced current in tissue, not heating.

Sources

1. icnirp-2010 Guidelines for Limiting Exposure to Time-Varying Electric and Magnetic Fields (1 Hz to 100 kHz) — International Commission on Non-Ionizing Radiation Protection, 2010. guideline, link checked 2026-08-12.
2. who-elf Electromagnetic fields and public health: exposure to extremely low frequency fields — World Health Organization, 2007. government, link checked 2026-08-12.