# NIOSH Pocket Guide to Chemical Hazards
Dioxane | CAS 123-91-1
C4H8O2 | RTECS JG8225000
Synonyms & Trade Names Diethylene dioxide; Diethylene ether; Dioxan; p-Dioxane; 1,4-Dioxane | DOT ID & Guide 1165 127
Exposure Limits | NIOSH REL: Ca C 1 ppm (3.6 mg/m3) [30-minute] See Appendix A
OSHA PEL†: TWA 100 ppm (360 mg/m3) [skin]
IDLH Ca [500 ppm] | Conversion 1 ppm = 3.60 mg/m3
Physical Description Colorless liquid or solid (below 53°F) with a mild, ether-like odor.
MW: 88.1 | BP: 214°F | FRZ: 53°F | Sol: Miscible
VP: 29 mmHg | IP: 9.13 eV |  | Sp.Gr: 1.03
Fl.P: 55°F | UEL: 22% | LEL: 2.0% |
Class IB Flammable Liquid: Fl.P. below 73°F and BP at or above 100°F.
Incompatibilities & Reactivities Strong oxidizers, decaborane, triethynyl aluminum
Measurement Methods NIOSH 1602; OSHA 7
Personal Protection & Sanitation Skin: Prevent skin contact Eyes: Prevent eye contact Wash skin: When contaminated Remove: When wet (flammable) Change: No recommendation Provide: Eyewash, Quick drench | First Aid (See procedures) Eye: Irrigate immediately Skin: Water wash promptly Breathing: Respiratory support Swallow: Medical attention immediately
Respirator Recommendations NIOSH At concentrations above the NIOSH REL, or where there is no REL, at any detectable concentration: (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; drowsiness, headache; nausea, vomiting; liver damage; kidney failure; [potential occupational carcinogen]
Target Organs Eyes, skin, respiratory system, liver, kidneys Cancer Site [in animals: lung, liver & nasal cavity tumors]
See also: INTRODUCTION