HYDROGEN SULFIDE†

Chemical Identification

CAS # 7783-06-4
Formula

H₂S

Synonyms

hydrosulfuric acid; sewer gas; stink damp

Physical Properties

Physical description Flammable, poisonous, colorless gas with a strong odor of rotten eggs.
Boiling point -76.59°F Molecular weight 34.08
Freezing point/melting point -121.88°F Vapor pressure 17.6 atm
Flash point Vapor density 1.09
Specific gravity 0.916@76°F Ionization potential 10.46eV
Lower explosive limit (LEL) 4.3% Upper explosive limit (UEL) 45%
NFPA health rating 4 NFPA fire rating 4
NFPA reactivity rating 0 NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA

Analyte code (IMIS no.) 1480 1480
Sampling group
Sampler/Sampling media Silica gel coated with silver nitrate and a glass fiber filter treated with sodium carbonate/glycerol, 2, (200/200 mg) [SKC 226-177]; calibration adapter kit Dräger X-am 5600 Multi-Gas Detector with a Dräger XXS H2S LC electrochemical sensor
Sampling time*

240 min

Sampling volume (TWA)*

12 L

Sampling flow rate (TWA)*

0.05 L/min

Sampling volume (STEL/Peak/C)*

7.5 L (C), 5 L (Peak)

Sampling flow rate (STEL/Peak/C)*

0.05 L/min

Analytical method instruments IC
Method reference OSHA 1008 (fully validated) OSHA 1028 (fully validated)
Notes

The sampling pump must be capable of maintaining a constant flow of 0.5 L/min with a back pressure of approximately 20 inches of water. The GFF filters are analyzed by a similar but modified procedure (NIOSH 6004) for SO₂ if requested.

Do not use this method when dimethyl disulfide, dimethyl sulfide, and any mercaptans are present

Special requirements

* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method

Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques

Device Detector tube Detector tube Detector tube CMS Chips CMS Chip CMS Chip
Model/Type Dräger - Hydrogen Sulfide 1/d, 8101831 Gastec 4LL Matheson-Kitagawa 8014-120SD Hydrogen sulfide, 0.2-5 ppm range; Hydrogen sulfide, 2-50 ppm range Hydrogen sulfide, 20-500 ppm range Hydrogen sulfide, 100-2500 ppm range
Sampling information
(see manufacturer instructions)
1/10 strokes, 0.5-200 ppm range, approx 25% uncertainty 0.5 to 10 strokes, 0.1-120 ppm range, approx 8% uncertainty for 2.5-60 ppm 0.5/1 strokes, 0.5-60 ppm range

Exposure Limits

OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
NIOSH REL
Up to 10-hour TWA
(ST) STEL
(C) Ceiling
ACGIH TLV©
8-hour TWA
(ST) STEL
(C) Ceiling
CAL/OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
PEL-TWA REL-TWA TLV-TWA
 

1 ppm [2009]

PEL-TWA
 

10 ppm (14 mg/m³)

PEL-STEL REL-STEL TLV-STEL
 

5 ppm [2009]

PEL-STEL
 

15 ppm (21 mg/m³)

PEL-C

20 ppm (C), 50 ppm (Peak) [10 min, once only, if no other measurable exposure occurs]

REL-C

10 ppm (15 mg/m³) [10 min]

TLV-C
 

 

PEL-C
 

50 ppm

Skin notation

N

Skin notation

N

Skin notation
 

N

Skin notation
 

N

Notes:

See 29 CFR 1910.1000, Table Z-2. OSHA Construction and Maritime Industries PEL is 10 ppm (15 mg/m³), as an 8 hr TWA. See 29 CFR 1926.55 Table 1 and 29 CFR 1915.1000 Table Z-Shipyards.

Notes: Notes:
 

 

Notes:
 

 

Health factors:  See NIH-NLM PubChem. IDLH
 

100 ppm

Carcinogenic classifications: Not listed Notes:
 

 

AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
 

0.1 ppm/30 ppm/100 ppm

Additional Resources and Literature References

Last Updated Date : 11/01/2024