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Hexamethylene diisocyanate

Synonyms & Trade Names
1,6-Diisocyanatohexane, HDI, Hexamethylene-1,6-diisocyanate, 1,6-Hexamethylene diisocyanate, HMDI
CAS No.
822-06-0
RTECS No.
DOT ID & Guide
2281 156
Formula
OCN[CH₂]₆NCO
Conversion
1 ppm = 6.88 mg/m3
IDLH
N.D.
See: IDLH INDEX
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
Measurement Methods
NIOSH 5521 , 5522 , 5525;
OSHA 42
See: NMAM or OSHA Methods
Physical Description
Clear, colorless to slightly yellow liquid with a sharp, pungent odor.
Molecular Weight
168.2
Boiling Point
415°F
Freezing Point
-89°F
Solubility
Low (Reacts)
Vapor Pressure
(77°F): 0.05 mmHg
Ionization Potential
?
Specific Gravity
(77°F): 1.04
Flash Point
284°F
Upper Explosive Limit
?
Lower Explosive Limit
?
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).]
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
Personal Protection/Sanitation
(See protection codes)
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

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0278
Page last reviewed: October 30, 2019