As the laser power increases, the risk of eye injury also increases. At the high
end, around 250 to 500 milliwatts, even a brief exposure could cause retinal
damage.
Avoid all eye exposure to beams from Class 3B lasers.
This includes
unintentional or accidental exposures. Be careful to keep the beam away
from eyes and faces.
Also, remember that reflections off mirrors, glass, and shiny surfaces can be
just as hazardous as the direct beam.
Avoid reflected Class 3B beams the
same way you would avoid the direct beam.
The Nominal Ocular Hazard Distance (NOHD) for a lower-powered 50 mW
Class 3B visible-beam laser with a tight beam (0.5 milliradian divergence) is
330ft (100 m).
If you are closer than the NOHD distance to the laser, there is a possibility of
retinal damage if the direct or reflected beam enters the eye. The closer you
are to the laser and the longer the beam is in the eye, the greater the chance
of injury.
Class 3B Laser skin injury hazards
A Class 3B laser is not normally considered a skin or materials burn hazard.
However, if the laser “dot” is kept motionless on skin at close range, heat can
be felt. The more powerful the Class 3B laser, the sooner the heat will build
up.
Do not deliberately attempt to burn skin.
This can be very painful, can take
a long time to heal, and can leave a permanent scar.
Class 3B Laser protective eyewear
Laser glasses or goggles are suggested for lower-powered Class 3B lasers,
and are recommended for higher-powered Class 3Bs. They should be
selected to protect against the laser’s power and wavelength.
The eyewear should not block out all of the laser’s light. This is because it is
necessary to see where the laser “dot” is in order to safely work with the
laser. Because the eyewear is blocking some or perhaps all of the laser’s light
(for example, a hazardous reflection) you should still use caution even when
using the laser protective eyewear.
As you use the laser, any other persons in the area should also have the same
type of laser protective eyewear as you.
DO NOT USE SUNGLASSES FOR LASER PROTECTION.
User Guide
August 2018
8
