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 https://www.osha.gov.

December 5, 1978

Mr. Glenn T. Carninev
TSCA Coordinator
McGean Chemical Company, Inc.
1250 Terminal Tower
Cleveland, Ohio 44113

Dear Mr. Carnine:

This is in response to your letter to Mr. Gail Brinkerhoff in which you state your view about the applicability of 29 CFR 1910.1018 (the standard for occupational exposure to inorganic arsenic, published in the Federal Register on May 5, 1978) to the manufacture of antimony oxide by the fuming process. Please accept my apology for the delay.

The arsenic containing species you mention as becoming airborne during the process is an inorganic compound containing arsenic. In accordance with the definition under 29 CFR 1910.1018(b), all such species are "inorganic arsenic". Since your discussion indicates that there is a significant potential for exposure to an inorganic arsenic compound, 29 CFR 1910.1018 applies to the manufacture of antimony oxide by the fuming process.

Chemical reactivity is not a criterion that determines whether an "inorganic arsenic" compound is exempt from 29 CFR 1910.1018. A determining criterion is the propensity for an "inorganic arsenic" compound to find its way into the body.

For example, 29 CFR 1910.1018 does not apply when light emitting diodes containing gallium arsenide conductors are assembled into calculators or watches. That is because only minimal gallium arsenide will either rub off onto the hands or volatilize during the process.

Thank you for your interest in occupational health.

Sincerely,



Irving Weisblatt
Acting Director
Federal Compliance
and State Programs