- Methanoic acid
- Hydrogencarboxylic acid
- Aminic acid
- Formylic acid
Clear, colorless liquid that may fume, with an intense, pungent, penetrating odor.
Manufacture of fumigants.
Registry Numbers and Inventories.
EC Index Number
S 23 26 45
Tumorigen; Mutagen; Human Data; Primary Irritant
Swiss Giftliste 1
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Vapor pressure, mmHg
34 (20 C)
Vapor density (air=1)
4.4% at 20 C
2.1 (butyl acetate = 1)
Odor Threshold Odor threshold 0.063 ppm
1.2183 g/cm3 (20 C)
Solubility in water
1.789 cp (20 C)
37.13 g/s2 @ 25 C
1.3714 (20 C)
58.5 (16 C)
Partition coefficient, pKow
Heat of fusion
Heat of vaporization
Heat of combustion
Hazards and Protection.
Store in a tightly closed container. Keep from contact with oxidizing materials. Store in a cool, dry, well-ventilated area away from incompatible substances. Corrosives area. Do not store in metal containers. Do not store near alkaline substances. Vent periodically
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use only in a well ventilated area. Contents may develop pressure upon prolonged storage. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Keep container tightly closed. Do not get on skin or in eyes. Do not ingest or inhale. Discard contaminated shoes. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
Rubber or neoprene gloves and additional protection including impervious boots, apron, or coveralls, as needed in areas of unusual exposure. Use chemical safety goggles and/or a full face shield where splashing is possible. Maintain eye wash fountain and quick-drench facilities in work area.
Wear a supplied air, full-facepiece respirator, airlined hood, or full-facepiece self-contained breathing apparatus. Breathing air quality must meet the requirements of the OSHA respiratory protection standard (29CFR1910.134). Formic acid has questionable warning properties and a low IDLH. Respirator recommended to 6 times the TLV value as a maximum.
Large spills may be neutralized with dilute alkaline solutions of soda ash, or lime. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Absorb spill using an absorbent, non-combustible material such as earth, sand, or vermiculite. Use a spark-proof tool. Provide ventilation. Do not get water inside containers.
Stable under normal temperatures and pressures.
Sulfuric acid, strong caustics, furfuryl alcohol, hydrogen peroxide, strong oxidizers and bases. Reacts explosively with oxidizing agents.
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.
Upper exp. limit, %
Lower exp. limit, %
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use water spray to keep fire-exposed containers cool. Containers may explode in the heat of a fire. Extinguishing media: Do NOT get water inside containers. For small fires, use dry chemical, carbon dioxide, or water spray. For large fires, use dry chemical, carbon dioxide, alcohol-resistant foam, or water spray. Cool containers with flooding quantities of water until well after fire is out.
Moderately flammable. Combustion with moderate heating.
When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards. May polymerize explosively when involved in a fire. Contact with metals may evolve flammable hydrogen gas. Sensitive to static charge.
Toxic vapor generated in fires
OSHA PEL: TWA 5 ppm (9 mg/m3) NIOSH REL: TWA 5 ppm (9 mg/m3) NIOSH IDLH: 30 ppm
Prolonged or repeated skin contact may cause dermatitis. May cause liver and kidney damage. Effects may be delayed. Laboratory experiments have resulted in mutagenic effects.
Causes severe digestive tract burns with abdominal pain, vomiting, and possible death. May be harmful if swallowed. May cause central nervous system depression. Ingestion may produce corrosive ulceration and bleeding and necrosis of the gastrointestinal tract accompanied by shock and circulatory collapse.
May cause asthmatic attacks due to allergic sensitization of the respiratory tract. Causes chemical burns to the respiratory tract. Aspiration may lead to pulmonary edema. Vapors may cause dizziness, nausea, itching, burning, and swelling of the eyes.
May cause skin sensitization, an allergic reaction, which becomes evident upon re-exposure to this material. Contact with liquid is corrosive and causes severe burns and ulceration. Absorbed through the skin. May cause erythema and blistering.
Contact with liquid is corrosive to the eyes and causes severe burns. Lachrymator. May cause corneal edema, ulceration, and scarring.
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
Get medical aid immediately. Remove from exposure to fresh air immediately. If breathing is difficult, give oxygen. DO NOT use mouth-to-mouth respiration. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
Get medical aid immediately. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse. Destroy contaminated shoes.
Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed. Extensive irrigation is required (at least 30 minutes).