The information contained thereon is the property of SPDI, Inc. Reproduction or use in whole or in part of
this manual and the information thereon by anyone, except authorized persons in the furtherance of the
business SPDI, Inc. without the written consent of SPDI Inc. is STRICTLY PROHIBITED 4
UV Safety
Ultraviolet Safety…
The spectra available for ultraviolet curing and drying is quite varied. Coatings,
inks, and adhesives may be composed of formulations that require strong UV intensity of
various wavelengths. Longwave ultraviolet radiation (320-420 nanometers) is considered
most practical.
Shielding is absolutely mandatory. Medium pressure UV lamps radiate harmful UV
radiation that 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 radiations can cause severe burning of skin and eyes. UV burn
of the eyes affects the cornea that 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.
Exposure to UV radiations, of only limited time, 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 – high power UV radiation can cause severe burns to the skin.
Shielding material can be of cloth, glass, plastic, wood, or metal. As infrared
energy is generated along with intense visible light, fireproof as well as opaque material
that does not degenerate under UV radiation must be utilized.
Direct light from the UV processor should not be visible to the operator nor other
personnel. Bounce (reflected) light should be minimized and avoided. Total shielding
with openings minimized for product entrance and egress from the UV processor should
be incorporated into processor design. Reflective surfaces coated with black UV
absorbing paint reduce reflected UV radiations. Protective clothing and safety spectacles
should be worn if optimum shielding cannot be attained.
Thermal Safety…
Infrared energy, an inherent product of the arc utilized to create UV energy in UV
processors, can cause overheating of processor components when adequate safeguards
are not incorporated into the UV processor design and application.
Cooled heat sinks should provide protection to the press, conveyor, and other
process components in or near the UV processor. The cooling system should be
carefully designed and properly maintained. In air-cooled systems, filters must be
