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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.]
MW:
46.0
BP:
224°F (90% solution)
FRZ:
20°F (90% solution)
Sol:
Miscible
VP:
35 mmHg
IP:
11.05 eV
Sp.Gr:
1.22 (90% solution)		 Fl.P(oc): 122°F (90% solution)
UEL:
57% (90% solution)
LEL:
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

See also: INTRODUCTION   See ICSC CARD: 0485
 

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