TETRAHYDROFURAN | OSHA.gov | Occupational Safety and Health Administration

TETRAHYDROFURAN†

Chemical Identification
CAS #	109-99-9
Formula	C₄H₈O
Synonyms	diethylene oxide; 1,4-epoxybutane; tetramethylene oxide; THF

Physical Properties
Physical description	Colorless liquid with an ether-like odor.
Boiling point	151°F	Molecular weight	72.11
Freezing point/melting point	-163.3°F	Vapor pressure	132 mmHg
Flash point	6°F	Vapor density	2.5
Specific gravity	0.89	Ionization potential	9.45 eV
Lower explosive limit (LEL)	2%	Upper explosive limit (UEL)	11.8%
NFPA health rating	2	NFPA fire rating	3
NFPA reactivity rating	1	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	2390
Sampling group
Sampler/Sampling media	CSC tube (100/50 mg) [SKC 226-01]
Sampling time^*
Sampling volume (TWA)^*	1-9 L
Sampling flow rate (TWA)^*	0.01-0.2 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	GC-FID
Method reference	NIOSH 1609 (partially 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	Detector tube	Detector tube
Model/Type	Gastec 159	Gastec 161	Matheson-Kitagawa 8014-102SA	Matheson-Kitagawa 8014-162U
Sampling information (see manufacturer instructions)	1 or 2 strokes; 2-800 ppm range; uncertainty 25% for 50-200 ppm, 16% for 200-800 ppm	1 stroke; approx 0.03-1.4% range; uncertainty 16%	0.5 or 1 stroke; approx 0.01-5% range	1 stroke; approx 5-400 ppm 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	200 ppm (590 mg/m³)	REL-TWA	200 ppm (590 mg/m³)	TLV-TWA	50 ppm [2002]	PEL-TWA	200 ppm (590 mg/m³)
PEL-STEL		REL-STEL	250 ppm (735 mg/m³)	TLV-STEL	100 ppm [2002]	PEL-STEL	250 ppm (735 mg/m³)
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	Y	Skin notation	N
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes:		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	2000 ppm
Carcinogenic classifications: TLV-A3		Notes: 10% of LEL
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: 100 ppm/500 ppm/5000 ppm

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Tetrahydrofuran

NIOSH: Pocket Guide to Chemical Hazards - Tetrahydrofuran

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Tetrahydrofuran. See annual publication for most recent information.
Chhabra R.S., Herbert, R.A., Roycroft, J.H., Chou, B., Miller, R.A. and Renne, R.A.: Carcinogenesis studies of tetrahydrofuran vapors in rats and mice. Toxicol. Sci. 41(2): 183-188, 1998.
Food and Drug Administration: International Conference on Harmonization: final recommendations on the revision of the permitted daily exposures for two solvents, n-methylpyrrolidone and tetrahydrofuran, according to the maintenance procedures for the guidance Q3C Impurities: Residual Solvents; Availability. Notice. Fed. Regist. 68(219): 64352-64353, 2003.
Garnier, R., Rosenberg, N., Puissant, J.M., Chauvet, J.P. and Efthymiou, M.L.: Tetrahydrofuran poisoning after occupational exposure. Br. J. Ind. Med. 46(9): 677-678, 1989.
Pohanish, R.P. (editor): Tetrahydrofuran. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 2178-2180.

Last Updated Date : 01/13/2021

TETRAHYDROFURAN†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References