alpha-Methyl styrene
Synonyms & Trade Names
AMS [a-Methyl styrene], Isopropenyl benzene, 1-Methyl-1-phenylethylene, 2-Phenyl propyleneExposure Limits
NIOSH REL
TWA 50 ppm (240 mg/m3) ST 100 ppm (485 mg/m3)OSHA PEL
C 100 ppm (480 mg/m3) See Appendix GPhysical Description
Colorless liquid with a characteristic odor.Molecular Weight
118.2Boiling Point
330°FFreezing Point
-10°FSolubility
InsolubleVapor Pressure
2 mmHgIonization Potential
8.35 eVSpecific Gravity
0.91Flash Point
129°FUpper Exposive Limit
6.1%Lower Explosive Limit
1.9%Incompatibilities & Reactivities
Oxidizers, peroxides, halogens, catalysts for vinyl or ionic polymers; aluminum, iron chloride, copper [Note: Usually contains an inhibitor such as tert-butyl catechol.]Exposure Routes
inhalation, ingestion, skin and/or eye contactSymptoms
irritation eyes, skin, nose, throat; drowsiness; dermatitisTarget Organs
Eyes, skin, respiratory system, central nervous systemPersonal Protection/Sanitation
(See protection codes)Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:No recommendation
First Aid
(See procedures)Eye:Irrigate immediately
Skin:Water flush promptly
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations
NIOSH
Up to 500 ppm:
(APF = 10) Any chemical cartridge respirator with organic vapor cartridge(s)*
(APF = 10) Any supplied-air respirator*
Up to 700 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*
(APF = 50) Any chemical cartridge respirator with a full facepiece and organic vapor cartridge(s)
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
(APF = 25) Any powered, air-purifying respirator with organic vapor cartridge(s)*
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece
Emergency or planned entry into unknown concentrations or IDLH conditions:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus
Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
Any appropriate escape-type, self-contained breathing apparatus
- Page last reviewed:April 11, 2016
- Page last updated:April 11, 2016
- Content source:
- National Institute for Occupational Safety and Health (NIOSH) Education and Information Division