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Toluene-2,4-diisocyanate

Synonyms & Trade Names
TDI, 2,4-TDI, 2,4-Toluene diisocyanate
CAS No.
584-84-9
RTECS No.
DOT ID & Guide
2078 156
Formula
CH₃C₆H₃(NCO)₂
Conversion
1 ppm = 7.13 mg/m3
IDLH
Ca [2.5 ppm]
See: 584849
Exposure Limits
NIOSH REL
Ca See Appendix A
OSHA PEL
C 0.02 ppm (0.14 mg/m3) See Appendix G
Measurement Methods
NIOSH 2535 , 5521 , 5522 , 5525;
OSHA 18 , 33 , 42
See: NMAM or OSHA Methods
Physical Description
Colorless to pale-yellow solid or liquid (above 71°F) with a sharp, pungent odor.
Molecular Weight
174.2
Boiling Point
484°F
Melting Point
71°F
Solubility
Insoluble
Vapor Pressure
(77°F): 0.01 mmHg
Ionization Potential
?
Specific Gravity
1.22
Flash Point
260°F
Upper Explosive Limit
9.5%
Lower Explosive Limit
0.9%
Class IIIB Combustible Liquid: Fl.P. at or above 200°F.
Incompatibilities & Reactivities
Strong oxidizers, water, acids, bases & amines (may cause foam & spatter); alcohols [Note: Reacts slowly with water to form carbon dioxide and polyureas.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, nose, throat; choke, paroxysmal cough; chest pain, retrosternal (occurring behind the sternum) soreness; nausea, vomiting, abdominal pain; bronchitis, bronchospasm, pulmonary edema; dyspnea (breathing difficulty), asthma; conjunctivitis, lacrimation (discharge of tears); dermatitis, skin sensitization; [potential occupational carcinogen]
Target Organs
Eyes, skin, respiratory system
Cancer Site
[in animals: pancreas, liver, mammary gland, circulatory sys & skin tumors]
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated/Daily
Remove:When wet or contaminated
Change:Daily
Provide:Eyewash, Quick drench
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH

At concentrations above the NIOSH REL, or where there is no REL, at any detectable concentration:
(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: 0339   MEDICAL TESTS: 0233
Page last reviewed: October 30, 2019