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HYDROGEN SULFIDE†
| CAS # | 7783-06-4 |
|---|---|
| Formula |
H₂S |
| Synonyms |
hydrosulfuric acid; sewer gas; stink damp |
| 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 | |||
| 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.
| Wipe Sampler/Sampling media | |
|---|---|
| Bulk Method |
| 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 |
|
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 |
|||||
|---|---|---|---|---|---|---|---|
| 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:
|
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| Health factors: See NIH-NLM PubChem. | IDLH |
100 ppm |
|||||
| Carcinogenic classifications: Not listed |
Notes:
|
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|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
0.1 ppm/30 ppm/100 ppm |
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Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Hydrogen sulfide NIOSH: Pocket Guide to Chemical Hazards - Hydrogen sulfide Literature References
|
Last Updated Date : 11/01/2024