1,2,4-Trimethylbenzene

Synonyms & Trade Names
Asymmetrical trimethylbenzene, psi-Cumene, Hemimellitene [1,2,4-Trimethylbenzene], Pseudocumene [Note: Hemimellitene is a mixture of the 1,2,3-isomer with up to 10% of related aromatics such as the 1,2,4-isomer.]
CAS No.
95-63-6
RTECS No.
DOT ID & Guide
Formula
C₆H₃(CH₃)₃
Conversion
1 ppm = 4.92 mg/m3
IDLH
N.D.
See: IDLH INDEX
Exposure Limits
NIOSH REL
TWA 25 ppm (125 mg/m3)
OSHA PEL
none See Appendix G
Measurement Methods
OSHA PV2091
See: NMAM or OSHA Methods
Physical Description
Clear, colorless liquid with a distinctive, aromatic odor.
Molecular Weight
120.2
Boiling Point
337°F
Freezing Point
-77°F
Solubility
0.006%
Vapor Pressure
(56°F): 1 mmHg
Ionization Potential
8.27 eV
Specific Gravity
0.88
Flash Point
112°F
Upper Explosive Limit
6.4%
Lower Explosive Limit
0.9%
Class II Flammable Liquid
Incompatibilities & Reactivities
Oxidizers, nitric acid
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, nose, throat, respiratory system; bronchitis; hypochromic anemia; headache, drowsiness, lassitude (weakness, exhaustion), dizziness, nausea, incoordination; vomiting, confusion; chemical pneumonitis (aspiration liquid)
Target Organs
Eyes, skin, respiratory system, central nervous system, blood
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:Soap wash
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations
See also
INTRODUCTION   ICSC CARD: 1433
Page last reviewed: October 30, 2019