August 22, 2003

Ms. Nancy LeClerc
Safety and Environmental Coordinator
Marvin Windows & Doors
14835 Highway 17 West
Grafton, ND 58237

Dear Ms. LeClerc:

Thank you for your June 16 letter to the Occupational Safety and Health Administration's (OSHA's) Directorate of Enforcement Programs. This letter constitutes OSHA's interpretation only of the requirements discussed and may not be applicable to any questions not delineated within your original correspondence. You had specific questions regarding the use of portable vacuum cleaners for cleaning up aluminum and wood dust. The OSHA definitions of, and standards for, hazardous locations are contained in 29 CFR 1910.399 and 29 CFR 1910.307. Your paraphrased inquiry and our response follow.

Question: Is it acceptable to use portable wet/dry vacuum cleaners for cleaning up wood and aluminum dust and shavings?

Response: One of the situations that would classify an area as a Class II, Division 1 location, as defined at 29 CFR 1910.399, is if combustible dusts of an electrically conductive nature may be present. Aluminum dust is an electrically-conductive, particularly hazardous combustible dust, requiring any equipment used in that location would need to be approved for use in a Class II, Division 1 location. Therefore, if an unapproved vacuum-cleaning device is used to clean up aluminum dust, this is in violation of the provisions of 29 CFR 1910.307(b)(2) which require that equipment be approved for use in the hazardous location.

In your inquiry, you also asked about the appropriateness of using these devices to clean up wood dust, also a combustible dust. Wood dust can cause an area to be classified as a Class II or Class III hazardous location, depending on the particular conditions present. Therefore, any equipment used to clean up dust in that area would need to be approved for use in that hazardous location. It is the employer's responsibility to evaluate the area, determine, if necessary, the appropriate hazardous location classification, and ensure that only equipment approved for that location classification is used in that area.

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 General Industry Enforcement at (202) 693-1850.

Sincerely,

Richard E. Fairfax, Director
Directorate of Enforcement Programs