November 13, 2009

Mr. Gregory M. Olson, Jr.
TSI Incorporated
500 Cardigan Road
Shoreview, MN 55126

Dear Mr. Olson:

Thank you for your letter of May 15, 2009, regarding an equivalent nebulizer that TSI has developed for the saccharin solution and Bitrex™ (Denatonium benzoate) solution aerosol qualitative fit test (QLFT) protocols published in Appendix A of the Occupational Safety and Health Administration's (OSHA's) Respiratory Protection Standard, 29 CFR 1910.134. Your TSI QLFT Nebulizer replaces the DeVilbiss Nebulizer squeeze bulb required by both the saccharin and Bitrex QLFT protocols for generating the test aerosol concentration. The sensitivity and test aerosol concentrations, exercises, and other elements of the fit test protocols are not changed.

Using the TSI QLFT Nebulizer, in place of the squeeze bulb, is a modification to the saccharin and Bitrex QLFT protocols contained in Appendix A. However, based on the information you have provided, OSHA agrees that this modification by itself does not constitute the development of a new fit test method within the meaning of 29 CFR 1910.134, Appendix A, Part II. The saccharin and Bitrex protocols in Appendix A, Part I, paragraphs B.3 (a)(4) and (b)(4) and paragraphs B.4 (a)(4) and (b)(4), respectively, state that a "DeVilbiss Model 40 Inhalation Medication Nebulizer or equivalent" must be used to generate the sensitivity and test concentration aerosols. This requirement was discussed in the preamble as follows: "The final standard also does not restrict employers to using a DeVilbiss Model 40 Nebulizer but also allows them to use an equivalent test nebulizer" (63 Federal Register 1152-1230 (Jan. 8, 1998)). Based on the information you provided in your letter, OSHA agrees with you that this substitution by itself does not constitute the development of a new fit test method. Therefore, this substitution does not trigger the requirements in Appendix A, Part II - New Fit Test Protocols for section 6(b)(7) rulemaking. OSHA will consider the use of the TSI QLFT Nebulizer as an equivalent nebulizer to the squeeze bulb nebulizer when the saccharin or Bitrex QLFT protocols are properly performed under the Respiratory Protection Standard.

OSHA believes that proper training and written instructions for individuals operating your device are necessary to ensure proper fit testing. While OSHA will consider the TSI QLFT Nebulizer and DeVilbiss Nebulizer methods to be equivalent, the Agency will expect the operator to be knowledgeable in the conduct of the QLFT. More specifically, the operator should know the basic principles for performing a general saccharin or Bitrex fit test (e.g., instructing the subject to breathe through the mouth with the tongue slightly forward during the screening portion of the test), along with the knowledge necessary to successfully operate the TSI QLFT Nebulizer. Therefore, the fit test operator will need to be proficient in the use of the TSI QLFT Nebulizer, performing the QLFT standard operating procedure enclosed in your letter, and knowledgeable in any necessary additional written instructions when performing the QLFT.

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 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 at (202) 693-2190.

Sincerely,



Richard E. Fairfax, Director
Directorate of Enforcement Programs