Working with Lasers - STFC Safety Code No 22 (summary)
There are many lasers in the CLF that can cause permanent damage to the eye or burns to the skin through a momentary exposure to the beam or reflection.
Lasers emit beams of non-ionising radiation at wavelengths spanning the ultraviolet to the far infrared. For lasers in the visible or near infrared part of the spectrum there is a particular risk of damage to the retina of the eye, resulting in permanent visual impairment.
The power of laser beams, particularly pulsed lasers, can be so high that not only the main beam but also weak reflections and diffusely scattered radiation can be hazardous. Constant care and awareness is therefore needed at all times when working with lasers.
In a research laboratory there may be lasers operating at different wavelengths, fixed and variable, from the UV through the visible and IR. What may seem to be a steady beam may be a pulsed laser operating at a high pulse repetition rate with peak powers in the individual pulses that are more than a million times the average power of the beam. Apparently weak blue or red beams may be operating at wavelengths at the extreme of the visual response range of the eye where its sensitivity is several thousand times below its peak sensitivity (yellow light). UV and IR beams cannot be seen at all.