Electromagnetic (EM) Radiation Safety

X-Rays
few nm range
EHz range

Sources of X-rays used on campus covered under Ministry of Labour guidelines. X-Ray Safety Web Page covers topics in X-Ray Safety.

UV Radiation
180 nm - 400 nm
0.75 PHz - 3 PHz

Has health benefits at low levels; at higher levels, can cause adverse effects both directly and indirectly. Exposure limited to a total dose in a working day since damage can take several hours to present. Skin type plays a role in our response. Many drugs can affect our sensitivity to UV radiation.

Visible Radiation
380 nm - 700 nm
430 THz - 790 THz

Visible radiation obviously interacts with our visual system, but at very high levels, it can thermally damage our retinas and skin. Exposure limits are based on the radiance of visible light sources (W/cm²sr). These limits would usually be applied to arc lamps (xenon), plasmas and some LEDs capable of creating hazardous levels of visible radiation.

Infrared Radiation
700 nm - 1 mm
0.3 THz - 430 THz

Infrared radiation is perceived as radiant heat by our skin and as such is a thermal hazard at high levels. Like visible radiation, exposure limits are based on the radiance of these sources.
(Both Visible and Infrared Radiation hazards are covered under Incoherent Optical Radiation Hazards).

Radio Frequency
1 mm - km
3 kHz - 300 GHz

Radio-frequency (RF) sources, electric and magnetic fields, are predominantly thermal hazards. The exposure limits in this range are for acute (short-term) exposures since there is no scientific evidence of adverse biological effects from chronic or cumulative exposure to electric and magnetic fields emitted at these frequencies. Exposure limits for this spectral range are based on specific absorption rates (W/kg) and are provided in Canada’s Safety Code 6 (2009), where limits were established through evaluation of scientific literature.