FORMIC ACID | Occupational Safety and Health Administration

FORMIC ACID†

Chemical Identification
CAS #	64-18-6
Formula	CH₂O₂
Synonyms	hydrogen carboxylic acid; methanoic acid

Physical Properties
Physical description	Colorless liquid with a pungent, penetrating odor.
Boiling point	224°F (90% solution)	Molecular weight	46.02
Freezing point/melting point	20°F (90% solution)	Vapor pressure	35 mmHg
Flash point	122°F (90% solution, open-cup)	Vapor density	1.6
Specific gravity	1.22 (90% solution)	Ionization potential	11.05 eV
Lower explosive limit (LEL)	18% (90% solution)	Upper explosive limit (UEL)	57% (90% solution)
NFPA health rating	3	NFPA fire rating	2
NFPA reactivity rating	0	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1310
Sampling group
Sampler/Sampling media	Sorbent tube, silica gel, specially cleaned, 7 x 110-mm size, 2 (200/400 mg sorbent) with GS ends and WWGW separators [SKC 226-10-03]
Sampling time^*
Sampling volume (TWA)^*	1-24 L
Sampling flow rate (TWA)^*	0.05 - 0.2 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	IC
Method reference	NIOSH 2011 (partially validated)
Notes	Samples requesting formic acid must be shipped to the laboratory ASAP and kept cold.
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
Model/Type
Sampling information (see manufacturer instructions)

**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	5 ppm (9 mg/m³)	REL-TWA	5 ppm (9 mg/m³)	TLV-TWA	5 ppm [1965]	PEL-TWA	5 ppm (9 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL	10 ppm [1965]	PEL-STEL	10 ppm (19 mg/m³)
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:		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	30 ppm
Carcinogenic classifications: Not listed		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: 3 ppm/25 ppm/250 ppm

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Formic acid

NIOSH: Pocket Guide to Chemical Hazards - Formic acid

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Formic acid. See annual publication for most recent information.
Barceloux, D.G., et al.: American Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning. J. Toxicol. Clin. Toxicol. 40(4): 415-446, 2002.
Berode, M., Sethre, T., Läubli, T. and Savolainen, H.: Urinary methanol and formic acid as indicators of occupational exposure to methyl formate. Int. Arch. Occup. Environ. Health 73(6): 410-414, 2000.
d'Alessandro, A., Osterloh, J.D., Chuwers, P., Quinlan, P.J., Kelly, T.J. and Becker, C.E.: Formate in serum and urine after controlled methanol exposure at the threshold limit value. Environ. Health Perspect. 102(2): 178-181, 1994.
Pohanish, R.P. (editor): Formic Acid. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 1. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1186-1188.
Sigurdsson, J., Bjornsson, A. and Gudmundsson, S.T.: Formic acid burn-local and systemic effects. Report of a case. Burns Incl. Therm. Inj. 9(5): 358-361, 1983.

Last Updated Date : 12/29/2020

FORMIC ACID†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References