Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

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

August 27, 1991

Mr. Tom Ellis
Director of Sales and Marketing
Classic Systems, Inc.
P.O. Box 6130
Buffalo Shoals Road
Statesville, North Carolina 28677

Dear Mr. Ellis:

This is in response to your letter of June 19, in which you request Occupational Safety and Health Administration (OSHA) verification that your new spray booth, in consideration of the design information provided, meets or exceeds 29 CFR 1910.107 standards. You have provided limited information, that is, an isometric depiction, generally stated design features and air flow velocities at different locations of your spray booth, on which to determine compliance with OSHA standards. Notwithstanding sufficient information from the manufacturer, spray booth compliance with OSHA standards is determined at the work place.

Employers are subject to compliance with OSHA standards which address the safety and health of employees involving in workplace spray booth operations intended to confine finishing applications consisting of flammable or combustible materials. Applicable OSHA standards include not only 29 CFR 1910.107, which pertains to the prevention of workplace fire and explosion hazards but also 29 CFR 1910.1000, which pertains to prevention of harmful exposure of employees to workplace toxic and hazardous substances.

Originally, 29 CFR 1910.107 was adopted from the NFPA 33-1969, Standard for Spray Finishing Using Flammable and Combustible Materials. Although the NFPA has updated its standard since the 1969 edition, OSHA has not. As a result, the current NFPA 33-1969, Spray Application Using Flammable and Combustible Materials, reflects the most up-to-date state of the art concerning the prevention of fire and explosion hazards during spray finishing operations.

Under an OSHA policy for "de minimis violations", employers are allowed to abide by the most current consensus standard applicable to their operations, rather than with the standard in effect at the time of the inspection, when the employer's action provides equal or greater employee protection. De Minimis violations are violations of existing OSHA standards which have no direct or immediate relationship to safety or health. Such violations of the OSHA standards result in no citation, no penalty an no required abatement.

Employers who fully comply with the specifications and requirements of the NFPA 33-1989, concerning the recirculation of exhaust air to an occupied spray booth, would not be cited under 29 CFR 1910.107(d)(9) under the policy for de minimis violations. However, the quality of the respirable air in the booth must comply, at a minimum, with requirements set forth by 29 CFR 1910.1000 which establishes permissible exposure limits (PEL's).

Recirculating contaminated air within the spray booth to accumulate volatile organic compounds (VOC) emission for periodic incineration must be considered with respect to the intent of section 5(a)(1) of the OSH Act, which requires each employer to furnish to each of his employment which are free from recognized hazards that are causing or likely to cause death or serious physical harm to his employees. In determination of compliance with OSHA safety and health standards, personal protective clothing is considered supplemental to engineering controls and administration practices to protect employees from exposure to hazards in the workplace.


Patricia K. Clark, Director
Directorate of Compliance Programs