Hazards of Ultraviolet Radiation
Responsible Office: Environmental Health and Safety
Policy Type: Security and Safety
Policy Number: 813
Last Date Revised: 5/10/16
Many departments on campus have the occasion to use apparatus that produce ultraviolet radiation.This management procedure should be used as a guide so that necessary precaution will be taken to avoid UV radiation exposure.
Ultraviolet (UV) radiation is an invisible radiant energy produced naturally by the sun, and artificially by arcs operating at high temperatures.Artificial sources commonly found on campus include germicidal and black light lamps, carbon arcs, welding and cutting torches, electric arc furnaces, and other laboratory equipment.
Since the eyes and skin readily absorb UV radiation, they are particularly vulnerable to injury.The severity of radiation injury depends on factors which include exposure time, intensity of the radiation source, distance from the source, wavelength, sensitivity of the individual, and presence of sensitizing agents.
Sunburn is a common example of the effect of UV radiation on the skin.Since UV radiation is not visible, the person exposed to UV may not be aware of the hazard at the time of exposure.
Absorption of the radiation by the mucous membranes of the eye and eyelids can cause conjunctivitis.Lesions may also be formed on the cornea at high exposure levels.Such injuries usually manifest themselves 6 to 12 hours after exposure.
Protective measures are essential for persons exposed to high intensity UV sources.Goggles, face shields, and masks provide protection for the eyes; protective clothing and barrier creams minimize skin exposure.Shiny metal surfaces reflect UV radiation, and, when possible, should be removed from the work area.Reflections from lamp housings, walls, ceilings, and other surfaces may be reduced by coating these surfaces with a pigmented paint to low UV reflectance.Very high levels of UV should be enclosed, so as to shield those in the area.
Exposure to UV may be a cause of skin cancer. The following facts are known concerning UV radiation carcinogenesis:*
1.The incidence and prevalence of skin cancer correlate with decreasing geographic latitude, hence with the degree of insulation.
2.Over 90% of skin cancers occur in parts of the body exposed to sunlight.
3.The amount of pigmentation affects the incidence and prevalence of skin cancers.
4.Skin cancer is more prevalent in people who spend more time out of doors.
At this time, the relationship between UV radiation and the incidence of skin cancer is inconclusive.However, many studies substantiate the hypothesis that exposure to UV is related to the development of skin cancer.
*NIOSH Technical Report "Carcinogenic Properties of Ionizing and Nonionizing Radiation.Volume 1 - Optical Radiation."