Oce Arizona T220UV User Manual - page 21
UV Lamp Safety |
6/2/04
1-9
1.3
UV Lamp Safety
1.3.1
UV Safety
The Arizona T220UV printer is designed so that direct light from lamps is not visible
and bounce (reflected) light is minimized. UV lamps radiate harmful ultraviolet rays,
which can cause serious burns to skin and eyes. While thermal burns are felt
immediately, UV burns are not felt for several hours. Short exposure to lamp radiation
can cause severe burning of skin and eyes. UV burn of the eyes affects the cornea and
takes several days to heal. UV burn is identical to "Welder's burn" and will feel like sand
in the eyes that cannot be washed out. The discomfort is transitory. Extreme caution must
be taken - high power UV radiation can cause blindness.
Limited exposure to UV radiation will evoke erythema on normal skin. Such erythema
is transitory and will not produce blistering, nor tanning, as only a small amount of
radiation penetrates the Malpighian layer. Extreme caution must be taken since high
power UV radiation can cause severe burns to the skin.
The Arizona T220UV printer has a built-in interlock safety system that shuts down the
UV lights if the gantry doors are opened. This ensures that the operator is not exposed
to potentially harmful UV rays from the lamps. The section “Safety Interlocks” on
page 27 explains the interlock system and how it protects the operator from UV
exposure.
1.3.2
Handling UV lamps
Bare skin contact with the UV lamps must be avoided. Replacement lamps must be
wiped with the supplied cleaning solution before placing in service. Compounds from
the skin when heated on lamps operating at 600 to 850C will form permanent etching
(devitrification) on the quartz surface decreasing UV energy transmission. A
contaminated lamp eventually may overheat, causing premature failure.
When unpacking the lamps, the carton should be opened fully so lamp can be lifted out
of packaging with no twisting or pulling. Unpacking should take place in an area large
enough to eliminate the possibility of inadvertently striking lamp against walls, pillars,
pipes, beams or press machinery.
1.3.3
Ozone Safety
Tri-atomic oxygen or ozone (O3) is the only by-product of the UV lamp. It is formed by
oxygen being exposed to 254nm wavelengths of UV energy. Ozone is effectively
eliminated in the printing area by exhausting air from the cooling system of the T220UV.
Such exhausting involves no danger as the hot gas is very unstable and breaks down to
oxygen rapidly in ducting. Also, the Arizona T220UV printer is equipped with ozone
filters located above the fans in the gantry. These filters ensure that ozone is kept to a
minimal safe level.