Ethylene oxide

Synonyms & Trade Names

Dimethylene oxide, 1,2-Epoxy ethane, Oxirane

CAS No.

75-21-8

RTECS No.

KX2450000

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

Ethylene oxide

NIOSH REL

OSHA PEL

Follow NIOSH

NIOSH Homepage