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Oregon OSHA - 350 Winter Street NE Room 430 - Salem, Oregon 97301-3882
For Immediate Release
February 10, 2005
Contact for more Information:
Kevin Weeks, Public Information Officer, 503-947-7428

Oregon OSHA issues safety advisory on metal halide lamps

(Salem) The Department of Consumer and Business Services, Occupational Safety and Health Division (Oregon OSHA) today released a safety advisory to educate employers and workers about the hazard posed by ultraviolet (UV) light overexposures from broken metal halide lamps.

In November 2004, approximately 120 employees of a school district near Portland were attending a training meeting in a school gymnasium. Almost half of the employees present in the gymnasium reported eye and skin irritation or sought medical attention in the several days following the meeting. The source of alleged UV overexposure in the gymnasium was identified as a metal halide lamp with a broken protective cover.

An Oregon OSHA Hazard Alert is available for download from the Oregon OSHA Web site, www.orosha.org, in the “News Room” section under “Hazard Alerts” – the direct link to this page is http://www.orosha.org/hazards/hazard.htm

Light measurements were conducted in the gymnasium by Oregon OSHA and by an environmental contractor using a broken bulb similar to the one present on the day of the exposure incident. Readings from intact bulbs were within acceptable national standards, while radiation from directly beneath the broken lamp reached the maximum allowed daily exposure levels for UV radiation within eight minutes.

The source of the excessive light radiation was a 400-watt metal halide bulb with a damaged outer protective cover. The bulb’s inner quartz tube continued to function properly, and radiated light energy without the UV-filtering properties of the glass cover absorbing the UV radiation. This form of lamp is common in many large indoor or outdoor facilities where lighting is required to cover a broad area, for example, gymnasiums and auditoriums, large warehouses and warehouse retail stores, and sports facilities.

Oregon OSHA recommends that employers with facilities that utilize metal halide lamps follow several recommendations to protect workers or visitors, and prevent possible UV overexposures:

· Educate workers about the potential hazard of UV light overexposure.

· Regularly inspect overhead lights for cracks or breakage.

· Use self-extinguishing metal halide lamps. When breakage occurs, the lamp will shut down automatically as a precaution. Metal halide lamps utilizing this feature are commercially available.

· For existing lamps, consider an additional glass or plastic lens to screen UV rays. The additional protective lens fits under the light and envelope assembly of the light.

Additional safety data is contained within the 2005 National Electrical Code, Article 410.4 (E), including newly adopted requirements for lighting in sports, mixed-use and all-purpose facilities. A key requirement of the Code is that mercury vapor or metal halide lamps in such facilities must be fully enclosed behind a plastic or glass projective cover. Cages or external screens used to prevent a ball or object from striking the lamp are permitted to assist with protection, but the cage cannot substitute for the required glass or plastic cover.

Oregon OSHA is committed to partnering with employers and workers to keep Oregon’s injury rates low, and workers’ compensation costs under control. One of the best things an employer can do to prevent injuries is to properly train employees. Oregon OSHA offers free training, free safety and health consultations, and education and training materials from the OR-OSHA Resource Center.

Keep your employees and workplaces safe through a commitment to training, education and elimination of hazards. More safety-and-health resources are available on Oregon OSHA's Web site, www.orosha.org