Precautions : The following must always be observed while dealing with lasers.
1) Never look along a laser beam or expose any part of your skin to it. Beware of reflected laser radiation. (Any surface which reflects light will also reflect a laser.)
Block out any reflected laser light with opaque matt grey screens.
2) Always wear the correct type of goggles for the particular laser being used. A helium-neon laser, for example, gives a red beam, and some lasers generate radiation in the ultraviolet and infra-red regions of the spectrum as well as producing visible light.
Never operate lasers in the dark. The room should always be brightly lit to avoid enlargement of the pupil of the eye.
Warning notices should be set up and the working area should be fenced off.
The laser source should be fixed rigidly to a bench so that the direction of the beam is not altered by accidental movement.
Never align a laser while it is switched on. This alignment should be carried out optically before turning on the source.
Keep laser instruments in a securely locked store room when they are not in use.