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2-METHYLBUTANE (ISOPENTANE)†
| CAS # | 78-78-4 |
|---|---|
| Formula |
C₅H₁₂ |
| Synonyms |
isopentane; ethyldimethylethane; isoamylhydride |
| Physical description | Watery colorless liquid with a gasoline-like odor. | ||
|---|---|---|---|
| Boiling point | 82°F | Molecular weight | 72.17 |
| Freezing point/melting point | -255.8°F | Vapor pressure | 689 mmHg |
| Flash point | -70°F | Vapor density | 2.48 |
| Specific gravity | 0.062 | Ionization potential | |
| Lower explosive limit (LEL) | 1.4% | Upper explosive limit (UEL) | 7.6% |
| NFPA health rating | 1 | NFPA fire rating | 4 |
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | R228 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | CSC tube (100/50 mg) [SKC 226-01] |
| Sampling time* | |
| Sampling volume (TWA)* | 4 L |
| Sampling flow rate (TWA)* | 0.2 L/min |
| Sampling volume (STEL/Peak/C)* | |
| Sampling flow rate (STEL/Peak/C)* | |
| Analytical method instruments | GC-FID |
| Method reference | NIOSH 1500 (partially validated) |
| Notes | |
| 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 | |||||
|---|---|---|---|---|---|
| Model/Type | |||||
|
Sampling information (see manufacturer instructions) |
|
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 |
1000 ppm (2950 mg/m³) |
REL-TWA |
120 ppm (350 mg/m³) |
TLV-TWA |
1000 ppm [2013] |
PEL-TWA |
600 ppm (1800 mg/m³) |
| PEL-STEL | REL-STEL |
|
TLV-STEL |
|
PEL-STEL |
|
|
| PEL-C | REL-C |
610 ppm (1800 mg/m³) [15 minutes] |
TLV-C |
|
PEL-C |
|
|
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
|
Notes:
As Pentane; there is no specific OSHA PEL for 2-Methylbutane. Construction and Maritime Industry PEL is 500 ppm (1500 mg/m³) as an 8 hr TWA for Pentane. See 29 CFR 1926.55 Table 1 and 29 CFR 1915.1000 Table Z-Shipyards. |
Notes:
as n-Pentane |
Notes:
as Pentane, all isomers |
Notes:
as Pentane |
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
1500 ppm (as n-Pentane) |
|||||
| Carcinogenic classifications: Not listed |
Notes:
|
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|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
|
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Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Isopentane NIOSH: Pocket Guide to Chemical Hazards - n-Pentane Literature References
|
Last Updated Date : 06/23/2023