# NIOSH Pocket Guide to Chemical Hazards
Hexamethylene diisocyanate | CAS 822-06-0
OCN[CH2]6NCO | RTECS MO1740000
Synonyms & Trade Names 1,6-Diisocyanatohexane; HDI; Hexamethylene-1,6-diisocyanate; 1,6-Hexamethylene diisocyanate; HMDI | DOT ID & Guide 2281 156
Exposure Limits | NIOSH REL: TWA 0.005 ppm (0.035 mg/m3) C 0.020 ppm (0.140 mg/m3) [10-minute]
OSHA PEL: none
IDLH N.D. | Conversion 1 ppm = 6.88 mg/m3
Physical Description Clear, colorless to slightly yellow liquid with a sharp, pungent odor.
MW: 168.2 | BP: 415°F | FRZ: -89°F | Sol: Low (Reacts)
VP(77°F): 0.5 mmHg | IP:? |  | Sp.Gr(77°F): 1.04
Fl.P: 284°F | UEL: ? | LEL: ? |
Class IIIB Combustible Liquid: Fl.P. at or above 200°F.
Incompatibilities & Reactivities Water, alcohols, strong bases, amines, carboxylic acids, organotin catalysts [Note: Reacts slowly with water to form carbon dioxide. Avoid heating above 392°F (polymerizes).]
Measurement Methods NIOSH 5521, 5522; OSHA 42
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: Soap flush immediately Breathing: Respiratory support Swallow: Medical attention immediately
Respirator Recommendations NIOSH Up to 0.05 ppm: (APF = 10) Any supplied-air respirator* Up to 0.125 ppm: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode* Up to 0.25 ppm: (APF = 50) Any self-contained breathing apparatus with a full facepiece/(APF = 50) Any supplied-air respirator with a full facepiece Up to 1 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
Exposure Routes inhalation, ingestion, skin and/or eye contact
Symptoms Irritation eyes, skin, respiratory system; cough, dyspnea (breathing difficulty), bronchitis, wheezing, pulmonary edema, asthma; corneal damage, skin blisters
Target Organs Eyes, skin, respiratory system
See also: INTRODUCTION