Methyl isocyanate
Synonyms & Trade Names
Methyl ester of isocyanic acid, MICExposure Limits
NIOSH REL
TWA 0.02 ppm (0.05 mg/m3) [skin]OSHA PEL
TWA 0.02 ppm (0.05 mg/m3) [skin]Physical Description
Colorless liquid with a sharp, pungent odor.Molecular Weight
57.1Boiling Point
102-104°FFreezing Point
-49°FSolubility
(59°F): 10%Vapor Pressure
348 mmHgIonization Potential
10.67 eVSpecific Gravity
0.96Flash Point
19°FUpper Exposive Limit
26%Lower Explosive Limit
5.3%Incompatibilities & Reactivities
Water, oxidizers, acids, alkalis, amines, iron, tin, copper [Note: Usually contains inhibitors to prevent polymerization.]Exposure Routes
inhalation, skin absorption, ingestion, skin and/or eye contactSymptoms
irritation eyes, skin, nose, throat; resp sensitization, cough, pulmonary secretions, chest pain, dyspnea (breathing difficulty); asthma; eye, skin damage; In Animals: pulmonary edemaTarget Organs
Eyes, skin, respiratory systemPersonal Protection/Sanitation
(See protection codes)Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet (flammable)
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 0.2 ppm:
(APF = 10) Any supplied-air respirator*
Up to 0.5 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*
Up to 1 ppm:
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece
Up to 3 ppm:
(APF = 2000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
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
Any appropriate escape-type, self-contained breathing apparatus
- Page last reviewed:April 11, 2016
- Page last updated:April 11, 2016
- Content source:
- National Institute for Occupational Safety and Health (NIOSH) Education and Information Division