Non-ionizing radiation in the workplace: radiofrequency radiation
This topic covers radiofrequency (RF) radiation as an occupational hazard: its frequency range, sources, biological effects and the methods used to control exposure.
Characteristics
- Radiofrequency radiation covers the frequency range from 300 Hz to 300 GHz. The corresponding wavelengths range from 1000 km to 1 mm.
- It is non-ionizing: its quantum energy is too low to ionize atoms or break chemical bonds.
- Sources: radar, microwave ovens, mobile telephones, television transmission, and FM and AM radio transmission (communication).
Effects
- Thermal effect: human tissue is irradiated and heated, because the energy is absorbed in the body. Tissues with poor heat loss and low blood flow, such as the lens of the eye and the testes, are most vulnerable.
- Non-thermal effect: induction of electrical currents in tissues (shocks, burns and similar effects).
- Further effects: at higher exposures local overheating, cataract, burns from contact with energized metal objects, and functional complaints (headache, fatigue, sleep disturbance, irritability) in people exposed long term to fields; the dose is expressed as the specific absorption rate (SAR, W/kg) and field strength or power density.