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Isobutane

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Synonyms & Trade Names
2-Methylpropane [Note: Also see specific listing for n-Butane.]
CAS No.
75-28-5
RTECS No.
TZ4300000
DOT ID & Guide
1075 115
1969 115
Formula
CH₃CH(CH₃)₂
Conversion
1 ppm = 2.38 mg/m3
IDLH
N.D.
See: IDLH INDEX
Exposure Limits
NIOSH REL
TWA 800 ppm (1900 mg/m3)
OSHA PEL
none See Appendix G
Measurement Methods
None available
See: NMAM or OSHA Methods
Physical Description
Colorless gas with a gasoline-like or natural gas odor. [Note: Shipped as a liquefied compressed gas. A liquid below 11°F.]
Molecular Weight
58.1
Boiling Point
11°F
Freezing Point
-255°F
Solubility
Slight
Vapor Pressure
(70°F): 3.1 atm
Ionization Potential
10.74 eV
Flash Point
NA (Gas)
Upper Explosive Limit
8.4%
Lower Explosive Limit
1.6%
Relative Gas Density
2.06
Flammable Gas
Incompatibilities & Reactivities
Strong oxidizers (e.g., nitrates & perchlorates), chlorine, fluorine, (nickel carbonyl + oxygen)
Exposure Routes
inhalation, skin and/or eye contact (liquid)
Symptoms
drowsiness, narcosis, asphyxia; liquid: frostbite
Target Organs
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

Not available.

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0901
Page last reviewed: October 30, 2019
Content source: National Institute for Occupational Safety and Health