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Hydrogen sulfide																				Related Pages
Synonyms & Trade Names
			Hydrosulfuric acid, Sewer gas, Sulfuretted hydrogen
CAS No.
			7783-06-4
	RTECS No.
			MX1225000
	DOT ID & Guide
			1053 117

FormulaH2S
	Conversion
			1 ppm = 1.40 mg/m3
	IDLH
			100 ppmSee: 7783064

Exposure Limits
			NIOSH RELC 10 ppm (15 mg/m3) [10-minute]
					OSHA PEL C 20 ppm 50 ppm [10-minute maximum peak] See Appendix G
	Measurement Methods
			**NIOSH** 6013;**OSHA** ID141
					
					See: NMAM or OSHA Methods
										
Physical Description
			Colorless gas with a strong odor of rotten eggs.
					[Note: Sense of smell becomes rapidly fatigued & can NOT be relied upon to warn of the continuous presence of H2S. Shipped as a liquefied compressed gas.]													
										
Molecular Weight34.1	
	Boiling Point-77°F
	Freezing Point-122°F
	Solubility0.4%
	Vapor Pressure17.6 atm
	Ionization Potential10.46 eV											
Flash PointNA (Gas)
	Upper Explosive Limit44.0%
	Lower Explosive Limit4.0%
	Relative Gas Density1.19
Flammable Gas
Incompatibilities & Reactivities
			Strong oxidizers, strong nitric acid, metals
Exposure Routes
			inhalation, skin and/or eye contact
Symptoms
			irritation eyes, respiratory system; apnea, coma, convulsions; conjunctivitis, eye pain, lacrimation (discharge of tears), photophobia (abnormal visual intolerance to light), corneal vesiculation; dizziness, headache, lassitude (weakness, exhaustion), irritability, insomnia; gastrointestinal disturbance; liquid: frostbite
Target Organs
			Eyes, respiratory system, central nervous system
										
Personal Protection/Sanitation
			(See protection codes) **Skin:**Frostbite
							**Eyes:**Frostbite
							**Wash skin:**No recommendation
							**Remove:**When wet (flammable)
							**Change:**No recommendation
							**Provide:**Frostbite wash
	First Aid
			(See procedures)**Eye:**Frostbite
							**Skin:**Frostbite
							**Breathing:**Respiratory support
Respirator Recommendations
			**NIOSH****Up to 100 ppm**: (APF = 25) Any powered, air-purifying respirator with cartridge(s) providing protection against the compound of concern(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concern(APF = 10) Any supplied-air respirator*(APF = 50) Any self-contained breathing apparatus with a full facepiece**Emergency or planned entry into unknown concentrations or IDLH conditions:** (APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus**Escape:** (APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concernAny appropriate escape-type, self-contained breathing apparatus
				Important additional information about respirator selection
See also
			INTRODUCTION
					  ICSC CARD: 0165

			
							

			Page last reviewed:  October 30, 2019						Content
							source: 	National Institute for Occupational Safety and Health NIOSH Pocket Guide to Chemical Hazards
Introduction
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Appendices
A – NIOSH Potential Occupational Carcinogens
B – Thirteen OSHA-Regulated Carcinogens
C – Supplementary Exposure Limits
D – Substances with No Established RELs
E – OSHA Respirator Requirements for Selected Chemicals
F – Miscellaneous Notes
G – 1989 Air Contaminants Update Project: Exposure Limits NOT in Effect
Type C & CE – Definitions for Type C and Type CE Respirators
Personal Protection and Sanitation Codes
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