- Safety and Health Topics
- Hydrogen Sulfide
Hydrogen sulfide exposure addressed in specific OSHA standards for general industry, shipyard employment and construction. This section highlights OSHA standards and documents related to hydrogen sulfide.
General Industry (29 CFR 1910)
|Subpart G – Occupational Health and Environmental Control||1910.94, Ventilation|
|Subpart H – Hazardous Materials||1910.119, Process safety management of highly hazardous chemicals||Subpart I – Personal Protective Equipment|
|1910.134, Respiratory protection|
|Subpart J – General Environmental Controls||1910.146, Permit-required confined spaces|
|Subpart Z – Toxic and Hhazardous Substances||1910.1000, Air contaminants|
|1910.1200, Hazard communication|
|1910.1450, Occupational exposure to hazardous chemicals in laboratories|
Maritime (29 CFR 1915, 1917, 1918)
|1915 Subpart B – Confined and Enclosed Spaces and Other Dangerous Atmospheres in Shipyard Employment||1915.12, Precautions and the order of testing before entering confined and enclosed spaces and other dangerous atmospheres|
|1915 Subpart Z – Toxic and Hazardous Substances||1915.1000, Air contaminants|
|1917 Subpart A – General Provisions||1917.1, Scope and applicability|
|1917 Subpart D – Specialized Terminals||1917.73, Terminal facilities handling menhaden and similar species of fish|
|1918 Subpart A – General Provisions||1918.1, Scope and application|
|1918.94(f), Ventilation and atmospheric conditions. Employees shall not enter the hold when the hydrogen sulfide level exceeds 20 ppm ceiling or when the oxygen content is less than 19.5 percent, except in emergencies.|
|1918 Subpart I – General Working Conditions||1918.94, Catch of menhaden and similar species of fish|
Construction (29 CFR 1926)
|Subpart D – Occupational Health and Environmental Controls||1926.55, Gases, vapors, fumes, dusts, and mists|
|Subpart S – Underground Construction, Caissons, Cofferdams, and Compressed Air||1926.800, Underground construction|
Additional Letters of Interpretation(supplementary guidance that clarifies the application of an established Agency policy or procedure)
Note: The “Letters of interpretation” bullets above link to letters related to each OSHA standard. The letters in this list provide additional information that is not necessarily connected to a specific OSHA standard highlighted on this Safety and Health Topics page.
- Post-emergency response and medical surveillance requirements of HAZWOPER. (August 5, 1993).
- Interpretation of OSHA requirements for personal protective equipment to be used during marine oil spill emergency response operations. (September 11, 1995).
- Potentially hazardous amine absorber pressure vessels used in refinery processing. (April 11, 1986).
- Interpretation of "high degree of acute toxicity" under the laboratory standard. (July 30, 1990).
- OSHA's policy on classification of a wet well as a Class 1, Division 1 location. (November 5, 1979).
- Fires involving spills or releases of hazardous substances. (June 17, 1991).
There are 28 OSHA-approved State Plans, operating state-wide occupational safety and health programs. State Plans are required to have standards and enforcement programs that are at least as effective as OSHA's and may have different or more stringent requirements.
Worker Exposure Limits (Enforceable)
- General Industry: 29 CFR 1910.1000 TABLE Z-2, Toxic and hazardous substances
Exposures must not exceed 20 parts per million (ppm) (ceiling) with the following exception: if no other measurable exposure occurs during the 8-hour work shift, exposures may exceed 20 ppm, but not more than 50 ppm (peak), for a single time period up to 10 minutes.
- Construction: 29 CFR 1926.55 Appendix A, Gases, vapors, fumes, dusts, and mists
Sets exposure limit of 10 ppm (15 mg/m3) time-weighted average (TWA)
- Shipyard: 29 CFR 1915.1000 Table Z, Air contaminants
Sets exposure limit of 10 ppm (15 mg/m3) TWA
Other Exposure Limits for Hydrogen Sulfide
NIOSH Recommended Exposure Limit (REL): 10 ppm, 10-minute ceiling
Concentration considered immediately dangerous to life and health (IDLH): 100 ppm
ACGIH® recommends a threshold limit value (TLV®) of 1 ppm as an 8-hour time weighted average (TWA) and a short-term exposure limit (STEL) of 5 ppm.
29 CFR 1910.119 App A, List of highly hazardous chemicals, toxics and reactives (mandatory). Hydrogen sulfide is included in these lists of toxic and reactive highly hazardous chemicals and is considered to present a potential for a catastrophic event at or above 1500 pounds.