February 26, 2003

James R. Bolton, Ph.D.
Executive Director and International Secretary
International Ultraviolet Association (IUVA)
628 Cheriton Crescent, N.W.
Edmonton, AB, Canada T6R 2M5

Dear Dr. Bolton:

Thank you for your December 20, 2002 letter to the Occupational Safety and Health Administration's (OSHA's) Directorate of Enforcement Programs (DEP). This letter constitutes OSHA's interpretation only of the requirements discussed and may not be applicable to any question not delineated within your original correspondence. You had a specific question about workplace exposure limits for ultraviolet radiation. We have responded to your paraphrased scenario and question below.

Scenario: Workers using ultraviolet (UV) lamps may have skin or eye exposure to stray ultraviolet light emissions. Such workers need to know acceptable levels of irradiance (measured in milliwatts per square centimeter (mW/cm²)) and how to monitor for stray radiation. The exposed UV dose would be in units of millijoules per square centimeter (mJ/cm²). [In most cases, the UV lamp would be a low pressure mercury lamp, so almost all the UV light is at 253.7 nanometers (nm).]

Question: Are there any OSHA regulations for workplace exposure limits to ultraviolet radiation?

Response: OSHA has two standards that cover employee exposure to radiation: Nonionizing Radiation (29 CFR 1910.97) and Ionizing Radiation (29 CFR 1910.1096). You may access a copy of our radiation standards from our website at http://www.osha.gov.

The non-ionizing radiation standard only covers the radio frequency region, including microwaves. The ionizing radiation standard covers alpha, beta, gamma, and X-rays; neutrons; high-speed electrons and protons; and other atomic particles; but does not include sound or radio waves, or visible, infrared, or ultraviolet light. Therefore, there are no OSHA-mandated employee exposure limits to ultraviolet radiation.

OSHA does provide technical guidance regarding protecting employees from ultraviolet light with respect to laser hazards. You can find this guidance in the (OSHA Technical Manual (TED 1-0.15A, Section III - Chapter 6)) on our website. The relevant chapter includes information on control measures and safety programs for laser hazards associated with exposure to ultraviolet light. Your association members may find this guidance useful.

Also, the American Conference of Governmental Industrial Hygienists (ACGIH), a non-governmental organization, has established allowable employee threshold limit recommendations (TLVs) for direct ocular and skin exposures to ultraviolet radiation. The values are published in the annual Threshold Limit Values for Chemical Substances and Physical Agents & Biological Exposure Indices. If you need a copy of the suggested allowable exposure limits to UV, please contact ACGIH directly. You may access the ACGIH's website at http://www.acgih.org or contact the organization at:

1330 Kemper Meadow Drive
Cincinnati, Ohio 45240-1634
Telephone: (513) 742-2020

Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA requirements are set by statute, standards, and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at http://www.osha.gov. If you have any further questions, please feel free to contact the Office of Health Enforcement of (202) 693-2190.

Sincerely,

Richard E. Fairfax, Director
Directorate of Enforcement Programs