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Styrene

Synonyms & Trade Names
Ethenyl benzene, Phenylethylene, Styrene monomer, Styrol, Vinyl benzene
CAS No.
100-42-5
RTECS No.
DOT ID & Guide
2055 128P(inhibited)
Formula
C₆H₅CH=CH₂
Conversion
1 ppm = 4.26 mg/m3
IDLH
700 ppm
See: 100425
Exposure Limits
NIOSH REL
TWA 50 ppm (215 mg/m3) ST 100 ppm (425 mg/m3)
OSHA PEL
TWA 100 ppm C 200 ppm 600 ppm (5-minute maximum peak in any 3 hours) See Appendix G
Measurement Methods
NIOSH 1501 , 3800;
OSHA 9 , 89
See: NMAM or OSHA Methods
Physical Description
Colorless to yellow, oily liquid with a sweet, floral odor.
Molecular Weight
104.2
Boiling Point
293°F
Freezing Point
-23°F
Solubility
0.03%
Vapor Pressure
5 mmHg
Ionization Potential
8.40 eV
Specific Gravity
0.91
Flash Point
88°F
Upper Explosive Limit
6.8%
Lower Explosive Limit
0.9%
Class IC Flammable Liquid: Fl.P. at or above 73°F and below 100°F.
Incompatibilities & Reactivities
Oxidizers, catalysts for vinyl polymers, peroxides, strong acids, aluminum chloride [Note: May polymerize if contaminated or subjected to heat. Usually contains an inhibitor such as tert-butylcatechol.]
Exposure Routes
inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms
irritation eyes, nose, respiratory system; headache, lassitude (weakness, exhaustion), dizziness, confusion, malaise (vague feeling of discomfort), drowsiness, unsteady gait; narcosis; defatting dermatitis; possible liver injury; reproductive effects
Target Organs
Eyes, skin, respiratory system, central nervous system, liver, reproductive system
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet (flammable)
Change:No recommendation
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Water flush
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: 0073   MEDICAL TESTS: 0214
Page last reviewed: October 30, 2019