Formic acid

Synonyms & Trade Names

Formic acid (85-95% in aqueous solution), Hydrogen carboxylic acid, Methanoic acid

CAS No.

64-18-6

RTECS No.

LQ4900000

DOT ID & Guide

1779 153

Formula

HCOOH

Conversion

1 ppm = 1.88 mg/m³

IDLH

30 ppm
See: 64186

Exposure Limits

NIOSH REL

TWA 5 ppm (9 mg/m³)

OSHA PEL

TWA 5 ppm (9 mg/m³)

Measurement Methods

NIOSH 2011;
OSHA ID186SG
See: NMAM or OSHA Methods

Physical Description

Colorless liquid with a pungent, penetrating odor. [Note: Often used in an aqueous solution.]

Molecular Weight

46.0

Boiling Point

224°F (90% solution)

Freezing Point

20°F (90% solution)

Solubility

Miscible

Vapor Pressure

35 mmHg

Ionization Potential

11.05 eV

Specific Gravity

1.22 (90% solution)

Flash Point

(oc) 122°F (90% solution)

Upper Explosive Limit

57% (90% solution)

Lower Explosive Limit

18% (90% solution)

Class II Combustible Liquid: Fl.P. at or above 100°F and below 140°F. (90% solution)

Incompatibilities & Reactivities

Strong oxidizers, strong caustics, concentrated sulfuric acid [Note: Corrosive to metals.]

Exposure Routes

inhalation, ingestion, skin and/or eye contact

Symptoms

irritation eyes; skin, throat; skin burns, dermatitis; lacrimation (discharge of tears); rhinorrhea (discharge of thin nasal mucus); cough, dyspnea (breathing difficulty); nausea

Target Organs

Eyes, skin, respiratory system

Personal 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

Important additional information about respirator selection

Formic acid

NIOSH REL

OSHA PEL

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