Lapse in Appropriations
For workplace safety and health, please call 800-321-6742; for mine safety and health, please call 800-746-1553; for Job Corps, please call 800-733-5627 and for Wage and Hour, please call 866-487-9243 (866-4-US-WAGE). This website is currently not being updated due to the suspension of Federal government services. The last update to the site was 10/1/2025. Updates to the site will start again when the Federal government resumes operations.
| # | Letters of Interpretation |
|---|---|
| 1 | - 1910.134 App A - QLFT fit testing procedures |
| 2 | - 1910.134 App A - Use of multi-station electric pump nebulizer and the squeeze bulb Bitrex for QLFT. |
| 3 | - 1910.134 App A - Appendix A requirements and techniques for fit testing respirators. |
| 4 | - 1910.134 App A - When to use quantitative and qualitative fit testing. |
| 5 | - 1910.134 App A - The grimace step in respiratory protection fit-testing procedures. |
| 6 | - 1910.134 App A - When to use qualitative or quantitative fit testing; storing SCBAs on fire trucks. |