Skip directly to search Skip directly to A to Z list Skip directly to navigation Skip directly to page options Skip directly to site content

alpha-Methyl styrene

Synonyms & Trade Names
AMS [a-Methyl styrene], Isopropenyl benzene, 1-Methyl-1-phenylethylene, 2-Phenyl propylene
CAS No.
98-83-9
RTECS No.
WL5075300
DOT ID & Guide
Formula
C₆H₅C(CH₃)=CH₂
Conversion
1 ppm = 4.83 mg/m3
IDLH
700 ppm
See: 98839
Exposure 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 G
Measurement Methods
NIOSH 1501;
OSHA 7
See: NMAM or OSHA Methods
Physical Description
Colorless liquid with a characteristic odor.
Molecular Weight
118.2
Boiling Point
330°F
Freezing Point
-10°F
Solubility
Insoluble
Vapor Pressure
2 mmHg
Ionization Potential
8.35 eV
Specific Gravity
0.91
Flash Point
129°F
Upper Exposive Limit
6.1%
Lower Explosive Limit
1.9%
Class II Combustible Liquid: Fl.P. at or above 100°F and below 140°F.
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 contact
Symptoms
irritation eyes, skin, nose, throat; drowsiness; dermatitis
Target Organs
Eyes, skin, respiratory system, central nervous system
Personal 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

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0732   MEDICAL TESTS: 0257

Follow NIOSH

NIOSH Homepage

TOP