Ethylene oxide (EC: 200-849-9)

CAS 75-21-8 C₂H₄O MW 44.1000 Danger 3 SDS documents available OSHA PEL listed NIOSH data available

NIOSH Potential Occupational Carcinogen

Flame

Gas Cylinder

Corrosion

Skull and Crossbones

Exclamation Mark

Health Hazard

Emergency: 911 | Poison Control: 1-800-222-1222

Safety Data Sheets

Manufacturer	Download
Sigma Aldrich	Download PDF
Syn Quest	Download PDF
TCI	Download PDF

Recommended safety equipment

Personal protective equipment commonly recommended for the hazard classes shown above.

As an Amazon Associate, DigitalMSDS earns from qualifying purchases.

Precautionary Statements

Code	Statement
`P203`	Obtain, read and follow all safety instructions before use.
`P210`	Keep away from heat, hot surface, sparks, open flames and other ignition sources. No smoking.
`P222`	Do not allow contact with air.
`P260`	Do not breathe dust/fume/gas/mist/vapors/spray.
`P261`	Avoid breathing dust/fume/gas/mist/vapors/spray.
`P264`	Wash hands [and ...] thoroughly after handling.
`P264+P265`	Wash hands [and ...] thoroughly after handling. Do not touch eyes.
`P270`	Do not eat, drink or smoke when using this product.
`P271`	Use only outdoors or in a well-ventilated area.
`P280`	Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/...
`P301+P316`	IF SWALLOWED: Get emergency medical help immediately.
`P301+P317`	IF SWALLOWED: Get medical help.
`P301+P330+P331`	IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.
`P302+P352`	IF ON SKIN: wash with plenty of water/...
`P302+P361+P354`	IF ON SKIN: Take off Immediately all contaminated clothing. Immediately rinse with water for several minutes.
`P304+P340`	IF INHALED: Remove person to fresh air and keep comfortable for breathing.
`P305+P351+P338`	IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses if present and easy to do - continue rinsing.
`P305+P354+P338`	IF IN EYES: Immediately rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing.
`P316`	Get emergency medical help immediately.
`P317`	Get emergency medical help.
`P318`	if exposed or concerned, get medical advice.
`P319`	Get medical help if you feel unwell.
`P321`	Specific treatment (see information on this label and safety datasheet)).
`P330`	Rinse mouth.
`P332+P317`	If skin irritation occurs: Get medical help.
`P337`	If eye irritation persists:
`P337+P317`	If eye irritation persists: Get medical help.
`P362+P364`	Take off contaminated clothing and wash it before reuse.
`P363`	Wash contaminated clothing before reuse.
`P377`	Leaking gas fire: Do not extinguish, unless leak can be stopped safely.
`P381`	In case of leakage, eliminate all ignition sources.
`P403`	Store in a well-ventilated place.
`P403+P233`	Store in a well-ventilated place. Keep container tightly closed.
`P405`	Store locked up.
`P410+P403`	Protect from sunlight. Store in a well-ventilated place.
`P501`	Dispose of contents/container to ...

Exposure Limits

OSHA PEL	1 ppm
NIOSH REL	0.1 ppm (Ceiling: 5 ppm)
NIOSH IDLH	800 ppm
Skin Notation	Yes — can be absorbed through skin

Physical Properties

Colorless gas or liquid (below 51°F) with an ether-like odor.

Boiling Point	51°F
Flash Point	-20°F (liquid)
Vapor Pressure	1.46 atm
Specific Gravity	0.82 (liquid at 50°F)

NFPA 704 Diamond

Target Organs

Reproductive

peritoneal cancer, leukemia, mutagenesis, reproductive effects

Synonyms

dimethylene oxide; 1,2-epoxyethane; oxirane; ETO

Data Sources

GHS Classification: PubChem CID 6354
OSHA PEL: OSHA Occupational Chemical Database
NIOSH REL/IDLH: NIOSH Pocket Guide

Disclaimer: This information is compiled from public regulatory databases for reference only. It does not replace the manufacturer's Safety Data Sheet (SDS). Always consult the official SDS for your specific product before handling chemicals.

See something wrong? Report a data issue.