NIOSH Pocket Guide to Chemical Hazards

Propionic acid CAS 79-09-4
Synonyms & Trade Names
Carboxyethane, Ethanecarboxylic acid, Ethylformic acid, Metacetonic acid, Methyl acetic acid, Propanoic acid
DOT ID & Guide
1848 132
NIOSH REL: TWA 10 ppm (30 mg/m3) ST 15 ppm (45 mg/m3)
OSHA PEL: none
IDLH N.D. Conversion 1 ppm = 3.03 mg/m3
Physical Description
Colorless, oily liquid with a pungent, disagreeable, rancid odor. [Note: A solid below 5°F.]
MW: 74.1
BP: 286°F
FRZ: 5°F
Sol: Miscible
VP: 3 mmHg
IP: 10.24 eV

Sp.Gr: 0.99
Fl.P: 126°F
UEL: 12.1%
LEL: 2.9%

Class II Combustible Liquid: Fl.P. at or above 100F and below 140F.
Incompatibilities & Reactivities
Alkalis, strong oxidizers (e.g., chromium trioxide) [Note: Corrosive to steel.]
Measurement Methods
None available
Personal Protection & Sanitation
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 To be added later
Exposure Routes inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms Irritation eyes, skin, nose, throat; blurred vision, corneal burns; skin burns; abdominal pain, nausea, vomiting
Target Organs Eyes, skin, respiratory system