Formic acid
Synonyms & Trade Names
Formic acid (85-95% in aqueous solution), Hydrogen carboxylic acid, Methanoic acidExposure Limits
NIOSH REL
TWA 5 ppm (9 mg/m3)OSHA PEL
TWA 5 ppm (9 mg/m3)Physical Description
Colorless liquid with a pungent, penetrating odor. [Note: Often used in an aqueous solution.]Molecular Weight
46.0Boiling Point
224°F (90% solution)Freezing Point
20°F (90% solution)Solubility
MiscibleVapor Pressure
35 mmHgIonization Potential
11.05 eVSpecific Gravity
1.22 (90% solution)Flash Point
(oc) 122°F (90% solution)Upper Exposive Limit
57% (90% solution)Lower Explosive Limit
18% (90% solution)Incompatibilities & Reactivities
Strong oxidizers, strong caustics, concentrated sulfuric acid [Note: Corrosive to metals.]Exposure Routes
inhalation, ingestion, skin and/or eye contactSymptoms
irritation eyes; skin, throat; skin burns, dermatitis; lacrimation (discharge of tears); rhinorrhea (discharge of thin nasal mucus); cough, dyspnea (breathing difficulty); nauseaTarget Organs
Eyes, skin, respiratory systemPersonal Protection/Sanitation
(See protection codes)Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:No recommendation
Provide:Eyewash, Quick drench
First Aid
(See procedures)Eye:Irrigate immediately
Skin:Water flush immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations
NIOSH/OSHA
Up to 30 ppm:
(APF = 10) Any supplied-air respirator*
(APF = 50) Any self-contained breathing apparatus 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 organic vapor canister having an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
Any appropriate escape-type, self-contained breathing apparatus
- Page last reviewed:April 11, 2016
- Page last updated:April 11, 2016
- Content source:
- National Institute for Occupational Safety and Health (NIOSH) Education and Information Division