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ELF (Extremely Low Frequency) Definition


Extremely Low Frequencies are those radio waves with frequencies between 3 and 30 Hz.

ELFs are a form of electromagnetic radiation.

A 3 Hz wavelength is 100,000 kilometers (62,137.12 miles) long.

One 3 Hz wave, from peak to peak, is 2.5 x the circumference of the earth.

A 30 Hz wavelength is 10,000 kilometers (6,213.712 miles) long.

One 30 Hz wave, from peak to peak, is the distance from San Frnacisco to Italy.

Typical ELF Magnetic Sources

  • electric transformers
  • electric utility meters
  • power lines
  • wiring

ELF Metal Shielding

Shield transformers and utility meters with highly-conductive and highly permeable metal. The shield is passive.

Shield power lines and wiring with active shielding that cancels the magnetic fields.

Typical ELF Electric Sources

  • power lines
  • fluorescent lighting

ELF Electric Shielding

Sheild power lines and fluorescent lighting with grounded conductive barriers such as metal screens.

ELF Protection Standards

The Occupational Safety and Health Admnistration does not conduct ELF safety audits.

“There are currently no specific OSHA standards that address extremely low frequency (ELF) fields.”

Return to the EMF Glossary page.