# 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
Exposure Limits | 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 73°F and below 100°F.
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
See also: INTRODUCTION