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Ethylene oxide

Synonyms & Trade Names
Dimethylene oxide, 1,2-Epoxy ethane, Oxirane
CAS No.
75-21-8
RTECS No.
DOT ID & Guide
1040 119P
Formula
C₂H₄O
Conversion
1 ppm = 1.80 mg/m3
IDLH
Ca [800 ppm]
See: 75218
Exposure Limits
NIOSH REL
Ca TWA <0.1 ppm (0.18 mg/m3) C 5 ppm (9 mg/m3) [10-min/day] See Appendix A
OSHA PEL
[1910.1047] TWA 1 ppm 5 ppm [15-minute Excursion]
Measurement Methods
NIOSH 1614 , 3800;
OSHA 30 , 49 , 50
See: NMAM or OSHA Methods
Physical Description
Colorless gas or liquid (below 51°F) with an ether-like odor.
Molecular Weight
44.1
Boiling Point
51°F
Freezing Point
-171°F
Solubility
Miscible
Vapor Pressure
1.46 atm
Ionization Potential
10.56 eV
Specific Gravity
0.82 (Liquid at 50°F)
Flash Point
NA (Gas) -20°F (Liquid)
Upper Explosive Limit
100%
Lower Explosive Limit
3.0%
Relative Gas Density
1.49
Flammable Gas
Incompatibilities & Reactivities
Strong acids, alkalis & oxidizers; chlorides of iron, aluminum & tin; oxides of iron & aluminum; water
Exposure Routes
inhalation, ingestion, (liquid), skin and/or eye contact
Symptoms
irritation eyes, skin, nose, throat; peculiar taste; headache; nausea, vomiting, diarrhea; dyspnea (breathing difficulty), cyanosis, pulmonary edema; drowsiness, lassitude (weakness, exhaustion), incoordination; EKG abnormal; eye, skin burns (liquid or high vapor concentration); liquid: frostbite; reproductive effects; ; In Animals: convulsions; liver, kidney damage [potential occupational carcinogen]
Target Organs
Eyes, skin, respiratory system, liver, central nervous system, blood, kidneys, reproductive system
Cancer Site
[peritoneal cancer, leukemia]
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact (liquid)
Eyes:Prevent eye contact (liquid)
Wash skin:When contaminated (liquid)
Remove:When wet (flammable)
Change:No recommendation
Provide:Quick drench (liquid)
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Water flush immediately
Breathing:Respiratory support
Swallow:Medical attention immediately (liquid)
Respirator Recommendations

(See Appendix E)

NIOSH

Up to 5 ppm:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concern†
(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 canister providing protection against the compound of concern†
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0155   MEDICAL TESTS: 0106
Page last reviewed: October 30, 2019