NIOSH Pocket Guide to Chemical Hazards

Isobutane CAS 75-28-5
CH3CH(CH3)2 RTECS TZ4300000
Synonyms & Trade Names
2-Methylpropane [Note: Also see specific listing for n-Butane.]
DOT ID & Guide
1075 115
1969 115
NIOSH REL: TWA 800 ppm (1900 mg/m3)
OSHA PEL†: none
IDLH N.D. Conversion 1 ppm = 2.38 mg/m3
Physical Description
Colorless gas with a gasoline-like or natural gas odor. [Note: Shipped as a liquefied compressed gas. A liquid below 11°F.]
MW: 58.1
BP: 11°F
FRZ: -255°F
Sol: Slight
VP(70°F): 3.1 atm
IP: 10.74 eV
RGasD: 2.06

Fl.P: NA (Gas)
UEL: 8.4%
LEL: 1.6%

Flammable Gas Class IA Flammable Liquid
Incompatibilities & Reactivities
Strong oxidizers (e.g., nitrates & perchlorates), chlorine, fluorine, (nickel carbonyl + oxygen)
Measurement Methods
None available
Personal Protection & Sanitation
Skin: Frostbite
Eyes: Frostbite
Wash skin: No recommendation
Remove: When wet (flammable)
Change: No recommendation
Provide: Frostbite
First Aid (See procedures)
Eye: Frostbite
Skin: Frostbite
Breathing: Respiratory support

Respirator Recommendations To be added later
Exposure Routes inhalation, skin and/or eye contact (liquid)
Symptoms Drowsiness, narcosis, asphyxia; liquid: frostbite
Target Organs central nervous system