PROPYLENE OXIDE (1,2-EPOXYPROPANE) | Occupational Safety and Health Administration

PROPYLENE OXIDE (1,2-EPOXYPROPANE)†

Chemical Identification
CAS #	75-56-9
Formula	C₃H₆O
Synonyms	1,2-epoxy propane; methyl ethylene oxide; methyloxirane; propene oxide; 1,2-propylene oxide

Physical Properties
Physical description	Colorless liquid with a benzene-like odor.
Boiling point	93.61°F	Molecular weight	58.08
Freezing point/melting point	-170°F	Vapor pressure	445 mmHg
Flash point	-35°F	Vapor density	2
Specific gravity	0.859 at 32°F	Ionization potential	9.81 eV
Lower explosive limit (LEL)	2.8%	Upper explosive limit (UEL)	37%
NFPA health rating	3	NFPA fire rating	4
NFPA reactivity rating	2	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	2215
Sampling group
Sampler/Sampling media	Anasorb 747 (140/70 mg) [SKC 226-81A]
Sampling time^*
Sampling volume (TWA)^*	5 L
Sampling flow rate (TWA)^*	0.1 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	GC-FID
Method reference	OSHA 88 (fully validated)
Notes
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Detector tube	Detector tube
Model/Type	Gastec 163	Matheson-Kitagawa 8014-163SA
Sampling information (see manufacturer instructions)	1 stroke, approx 0.03-3.9% range, uncertainty 25% for 0.06-1.3%, 16% for 1.3-3.9%	0.5 or 1 stroke, approx 0.05-5% range

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	100 ppm (240 mg/m³)	REL-TWA		TLV-TWA	2 ppm [2000]	PEL-TWA	2 ppm (4.75 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	N	Skin notation	N
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes: CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION (LOQ 8.4 ppm). See Appendix A, NIOSH Potential Occupational Carcinogens.		Notes: dermal sensitization (DSEN)		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	400 ppm
Carcinogenic classifications: IARC-2B, NIOSH-Ca, NTP-R, TLV-A3, EPA-B2		Notes: Ca
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: 50 ppm/250 ppm/750 ppm

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Propylene oxide

NIOSH: Pocket Guide to Chemical Hazards - Propylene oxide

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Propylene oxide. See annual publication for most recent information.
Czene, K., et al.: Analysis of DNA and hemoglobin adducts and sister chromatid exchanges in a human population occupationally exposed to propylene oxide: a pilot study. Cancer Epidemiol. Biomarkers Prev. 11(3): 315-318, 2002.
Faller, T.H., Csanady, G.A., Kreuzer, P.E., Bauer, C.M. and Filser, J.G.: Kinetics of propylene oxide metabolism in microsomes and cytosol of different organs from mouse, rat, and humans. Toxicol. Appl. Pharmacol. 172(1): 62-74, 2001.
Pohanish, R.P. (editor): Propylene Oxide. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1978-1980.

Last Updated Date : 01/11/2021

PROPYLENE OXIDE (1,2-EPOXYPROPANE)†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References