NIOSH Pocket Guide to Chemical Hazards

o-Xylene CAS 95-47-6
C6H4(CH3)2 RTECS ZE2450000
Synonyms & Trade Names
1,2-Dimethylbenzene; ortho-Xylene; o-Xylol
DOT ID & Guide
1307 130
NIOSH REL: TWA 100 ppm (435 mg/m3) ST 150 ppm (655 mg/m3)
OSHA PEL: TWA 100 ppm (435 mg/m3)
IDLH 900 ppm Conversion 1 ppm = 4.34 mg/m3
Physical Description
Colorless liquid with an aromatic odor.
MW: 106.2
BP: 292°F
FRZ: -13°F
Sol: 0.02%
VP: 7 mmHg
IP: 8.56 eV

Sp.Gr: 0.88
Fl.P: 90°F
UEL: 6.7%
LEL: 0.9%

Class IC Flammable Liquid: Fl.P. at or above 73F and below 100F.
Incompatibilities & Reactivities
Strong oxidizers, strong acids
Measurement Methods
NIOSH 1501, 3800; OSHA 1002
Personal Protection & Sanitation
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: Soap wash promptly
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations NIOSH/OSHA
Up to 900 ppm: (APF = 10) Any chemical cartridge respirator with organic vapor cartridge(s)*/(APF = 25) Any powered, air-purifying respirator with organic vapor cartridge(s)*/(APF = 10) Any supplied-air respirator*/(APF = 50) Any self-contained breathing apparatus 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
Exposure Routes inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms Irritation eyes, skin, nose, throat; dizziness, excitement, drowsiness, incoordination, staggering gait; corneal vacuolization; anorexia, nausea, vomiting, abdominal pain; dermatitis
Target Organs Eyes, skin, respiratory system, central nervous system, gastrointestinal tract, blood, liver, kidneys