- Methanesulfonic acid chloride
- Methylsulfonyl chloride
- Mesyl chloride
Pale yellow liquid.
Intermediate, flame-resistant products, stabilizer for liquid sulfur trioxide, biological chemicals.
Registry Numbers and Inventories.
very toxic, corrosive, dangerous for the environment
R 26 21/22 35 37
S 26 36/37/39 45
Mutagen; Primary Irritant
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Vapor pressure, mmHg
3 (25 C)
Vapor density (air=1)
1.48053 g/cm3 (18 C)
Solubility in water
1.451 (20 C)
Partition coefficient, pKow
Heat of vaporization
Hazards and Protection.
Store in a cool, dry place. Store in a tightly closed container. Corrosives area.
Wash thoroughly after handling. Avoid contact with eyes, skin, and clothing. Avoid ingestion and inhalation. Use only in a chemical fume hood.
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Clean up spills immediately, using the appropriate protective equipment. Provide ventilation.
Stable under normal temperatures and pressures.
Water - strong bases - oxidizing agents - alcohols.
Hydrogen chloride, carbon monoxide, oxides of sulfur, carbon dioxide.
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. Extinguishing media: Do NOT use water directly on fire. Use carbon dioxide or dry chemical.
May burn but does not ignite readily.
Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff. When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapors may travel to source of ignition and flash back. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water.
Fire will produce irritating, corrosive and/or toxic gases.
2 (Very strong toxins)
Causes gastrointestinal tract burns.
May cause irritation of the respiratory tract with burning pain in the nose and throat, coughing, wheezing, shortness of breath and pulmonary edema. Causes chemical burns to the respiratory tract. Inhalation may be fatal as a result of spasm, inflammation, edema of the larynx and bronchi, chemical pneumonitis and pulmonary edema.
Causes skin burns.
Causes eye burns. Lachrymator.
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. Treat symptomatically and supportively.
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
Get medical aid immediately. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Destroy contaminated shoes.
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.
2904 90 20
Std. Transport #