PAC Database - Detailed Chemical Data
Chemical Identity
| Chemical | CAS# | UN# | Health Code Numbers | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Methylpropane, 2-; (Isobutane) | 75-28-5 | 1969 |
17.00
4.08
4.05
7.01
8.00
1.00
4.06
4.11
|
|||||||||
| Formula | Synonyms | |||||||||||
| C4H10 | ISOBUTANE, 1,1-DIMETHYLETHANE, 2-METHYLPROPANE, A 31, A 31 (HYDROCARBON), ISO-BUTANE, ISOBUTANE (DOT FRENCH), ISOBUTANE EN MÉLANGE (DOT FRENCH), ISOBUTANE MIXTURE, ISOBUTANO (DOT SPANISH), ISOBUTANO, EN MEZCLA (DOT SPANISH), PROPANE, 2-METHYL, R 600A, TRIMETHYLMETHANE | |||||||||||
Physical Properties
| Mol Wt | State | MP (°C) | BP (°C) | VP (Hg) | VP (°C) | SG | LEL (ppm) |
|---|---|---|---|---|---|---|---|
| 58.12 | G | -159.4 | -11.73 | 750 | -12 | 0.551 | 18000 |
PAC Values
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 5500 | 17000 | 53000 |
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 13000 | 40000 | 130000 |
Technical Basis
A review of available sources identified AEGLs for a similar chemical, butane (CASRN: 106-97-8). These AEGLs were selected as the TEELs due to their usage priority among the emergency exposure limits (Section 1).
• TEEL-1 = AEGL-1 (butane, CASRN: 106-97-8)
• TEEL-2 = AEGL-2 (butane, CASRN: 106-97-8)
• TEEL-3 = AEGL-3 (butane, CASRN: 106-97-8)
This review generated TEEL values that are consistent with Rev. 29A.
Note: The butane AEGL-1 value require “safety considerations against the hazard(s) of explosion(s) ((≥10% LEL). Additionally, the butane AEGL-2 and AEGL-3 values exceeds its lower explosion limit (≥50% LEL for AEGL-2 and ≥100% LEL for AEGL-3) and are associated with “extreme safety considerations against the hazard(s) of explosion(s).” These statements should also be considered for 2-methylpropane (LEL = 1.6%).
• TEEL-1 = AEGL-1 (butane, CASRN: 106-97-8)
• TEEL-2 = AEGL-2 (butane, CASRN: 106-97-8)
• TEEL-3 = AEGL-3 (butane, CASRN: 106-97-8)
This review generated TEEL values that are consistent with Rev. 29A.
Note: The butane AEGL-1 value require “safety considerations against the hazard(s) of explosion(s) ((≥10% LEL). Additionally, the butane AEGL-2 and AEGL-3 values exceeds its lower explosion limit (≥50% LEL for AEGL-2 and ≥100% LEL for AEGL-3) and are associated with “extreme safety considerations against the hazard(s) of explosion(s).” These statements should also be considered for 2-methylpropane (LEL = 1.6%).
References
https://pubchem.ncbi.nlm.nih.gov/compound/Isobutane
https://www.epa.gov/aegl/butane-results-aegl-program
LEL: https://www.osha.gov/chemicaldata/577