Ultraviolet (UV) radiation is electromagnetic radiation covering a range of wavelengths from 100 to 400 nanometers (NM). Care should be taken to protect the skin and eyes from hazards related to acute and chronic UV exposures.
UV radiation is divided into 3 distinct spectral bands: UV-A, UV-B and UV-C.
UV-A radiation (315-400nm): Exposure to “Near UV” can produce a darkening of skin pigment (tanning) or erythema (sunburn). Chronic exposure to near UV can lead to toughening of the skin, suppression of the immune system and the formation of cataracts.
UV-B radiation (280-315nm): Exposure to “Middle UV” can cause erythema, photokeratitis (inflammation of the cornea), photoconjunctivitis (inflammation of the mucus membrane that lines the inner surface of the eyelid), cataracts, and skin cancer.
UV-C radiation (100-280nm): Exposure to “Far UV” can cause photokeratitis, photoconjunctivitis and corneal burns. The maximum effect on biological material in this spectral band occurs at 270nm.
Common UV generating equipment you can expect to see in a research setting includes transilluminators, UV sterilizers or germicidal lamps, black light lamps, phototherapy lamps and plasma radiation from cutting or welding equipment.
UV exposure standards
While there are no state or regulation that specify permissible UV exposure levels in a research or laboratory setting, the American Conference of Governmental Industrial Hygienists (AGIH) has established threshold limit values (TLV) to be used as a guide to protect against UV exposures. TLVs refer to UV radiation between 180nm-400nm and represent conditions that healthy workers may be exposed without any acute adverse health effects such as erythema or photoconjunctivitis. TLVs do not apply to UV lasers, photosensitive individuals or those using photosensitizing agents. Always refer to manuals provided by the manufacturer of the UV generating equipment for safe operating instructions.
Symptoms of an UV overexposure may not be immediately obvious. Skin burns or cataracts may take days or years to develop. If you believe a potential over exposure has occurred, or you develop skin/eye irritation after working with a UV source, seek medical attention at Campus Health Services. A professional should assess the severity of any potential injury. After seeking medical attention, complete the first report of injury (offered through UAccess) and notify Research Laboratory & Safety Services (RLSS). RLSS will review the incident and recommend or require corrective measures to avoid another over exposure.
RLSS maintains a calibrated UV radiometer and can make measurements for your application upon request. RLSS can further provide you with recommended exposure limits (based on the ACGIH guidelines) and can recommend PPE and other control measures to limit UV exposure. Contact RLSS to request an assessment or to schedule a UV radiation survey.
Protective Clothing: Wear a fully buttoned lab coat, long pants and closed toe shoes. Make sure that ALL skin is protected, including face, neck, hands and arms. Make sure there are no gaps in your protective clothing, especially at the wrist and neck areas.
Gloves: Wear disposable latex or nitrile gloves to protect exposed skin on the hands. Do not use vinyl gloves, which can transmit significant amounts of actinic UV.
Eye/Face Protection: Always wear a full face shield. To protect the eyes and face, use a polycarbonate face shield tamped with the ANSI Z87.1-1989 UV certification. Note: if you’re working with splash or projectile hazards, you may also need to wear safety glasses or goggles under the face shield.