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Chemical Datasheet

TOLUENE-2,4-DIISOCYANATE

6.1 - Poison

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 584-84-9   (TOLUENE-2,4-DIISOCYANATE)
  • 2078
  • Poison
  • TDI
NIOSH Pocket Guide International Chem Safety Card
Toluene-2,4-diisocyanate
  • 2,4-TOLUENE DIISOCYANATE
NFPA 704
Diamond Hazard Value Description
1
3 2
Blue Health 3 Can cause serious or permanent injury.
Red Flammability 1 Must be preheated before ignition can occur.
Yellow Instability 2 Readily undergoes violent chemical changes at elevated temperatures and pressures.
White Special
(NFPA, 2010)
General Description
Colorless to yellow or dark liquid or solid with a sweet, fruity, pungent odor. Melting point 68°F (20°C). Evolves CO2 when moist. This can cause over-pressurization in an enclosed space.Toxic and carcinogenic. Used in polyurethane foams, coatings in floor and wood finishes, sealers, paints, concrete sealers for aircraft and tank trucks, elastomers in clay pipe seals, elastomers and coatings, and crosslinking agent for nylon.

Rate of onset: Immediate

Persistence: Hours - weeks

Odor threshold: 0.4 - 2 ppm

Source/use/other hazard: Polyurethane (wood coatings, foam), nylon industries; skin irritant.

Hazards

Reactivity Alerts
Air & Water Reactions
Reacts with water with the evolution of carbon dioxide and formation of insoluble polyureas that are relatively nontoxic and inert [Merck 11th ed. 1989)].
Fire Hazard
When heated to decomposition it emits very toxic fumes of cyanide and nitrogen oxides. Reacts violently with amines, alcohol, bases and warm water causing fire and explosion hazards. Avoid strong oxidizers, water, acids, bases, amines, etc., cause foam and splatter. Avoid heating. Hazardous polymerization may occur. Concentrated alkaline compound such as sodium hydroxide or tertiary amines may cause run-away polymerization. Slow, not hazardous polymerization may occur above 235F. (EPA, 1998)
Health Hazard
Can cause death. Contact with skin may cause allergic eczema. Substance is very corrosive to eyes. Chronic exposure may cause chronic lung disease. As a vapor TDI is a powerful irritant to the respiratory tract. Chronic loss of respiratory function may occur. Acute asthmatic bronchitis or frank asthma may occur. A splash in the eyes of workmen has caused keratitis and conjunctivitis. This compound causes inflammation of the skin, also chemical pneumonitis and pulmonary edema. (EPA, 1998)
Reactivity Profile
TOLUENE-2,4-DIISOCYANATE is explosive in the form of vapor when exposed to heat, flame or sparks. Undergoes potentially violent polymerization reaction with strong bases or acyl chlorides. Reacts with water to liberate carbon dioxide. Potential explosion if stored in polyethylene containers due to absorption of water through the plastic. Emits very toxic fumes of oxides of nitrogen when heated to decomposition [Lewis, 3rd ed., 1993, p. 1251].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below.

Response Recommendations

Isolation and Evacuation
Excerpt from 156 Polymerizable warning [Substances - Toxic and/or Corrosive (Combustible / Water-Sensitive)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)
Firefighting
If water gets below the surface of the liquid, it will turn to steam and cause frothing. Full protective clothing, including self-contained breathing apparatus, rubber gloves, boots and bands around legs, arms, and waist should be provided. No skin surface should be exposed.

Move container from fire area if you can do it without risk. Cool containers that are exposed to flames with water from the side until well after fire is out. Dike fire control water for later disposal; do not scatter the material.

Water gently applied to surface or foam may cause frothing which will extinguish the fire.

If material is on fire or involved in fire do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, carbon dioxide or dry chemical. Use water spray to absorb vapor. (EPA, 1998)
Non-Fire Response
Caution : Mixing with water may result in a violent reaction. Sources of extreme heat or ignition including sparks or fire may result in formation of toxic nitrogen oxide gases.

Shut off ignition sources; no smoking or flames in hazard area. Do not touch spilled material; stop leak if you can do so without risk. Use water spray to reduce vapors.

Small spills: absorb with sand or other non-combustible absorbent material and place into containers for later disposal.

Small dry spills: with clean shovel place material into clean, dry container and cover; move containers from spill area.

Large spills: dike far ahead of spill for later disposal. Keep unnecessary people away; isolate hazard area and deny entry. Stay upwind; keep out of low areas. Ventilate closed spaces before entering them. If material is not on fire and not involved in fire; keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary; attempt to stop leak if without hazard. Use water spray to knock down vapors. If material is leaking (not on fire), downwind evacuation must be considered. (EPA, 1998)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Toluene-2,4-diisocyanate:

Skin: PREVENT SKIN CONTACT - Wear appropriate personal protective clothing to prevent skin contact.

Eyes: PREVENT EYE CONTACT - Wear appropriate eye protection to prevent eye contact.

Wash skin:
• WHEN CONTAMINATED - The worker should immediately wash the skin when it becomes contaminated.
• DAILY - The worker should wash daily at the end of each work shift, and prior to eating, drinking, smoking, etc.

Remove: WHEN WET OR CONTAMINATED - Work clothing that becomes wet or significantly contaminated should be removed and replaced.

Change: DAILY - Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premises.

Provide:
• EYEWASH - Eyewash fountains should be provided in areas where there is any possibility that workers could be exposed to the substances; this is irrespective of the recommendation involving the wearing of eye protection.
• QUICK DRENCH - Facilities for quickly drenching the body should be provided within the immediate work area for emergency use where there is a possibility of exposure. [Note: It is intended that these facilities provide a sufficient quantity or flow of water to quickly remove the substance from any body areas likely to be exposed. The actual determination of what constitutes an adequate quick drench facility depends on the specific circumstances. In certain instances, a deluge shower should be readily available, whereas in others, the availability of water from a sink or hose could be considered adequate.] (NIOSH, 2023)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Toluene diisocyanate, 2,4- 584-84-9 Liquid imm >480 >480 >480 >480 >480 >480 >480
Toluene diisocyanate, 2,4- (80%) 584-84-9 Liquid 60 >480 >480 >480 >480 >480 >480 >480
> indicates greater than.
"imm" indicates immediate; having a normalized breakthrough time of 10 minutes or less.

Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...

(DuPont, 2023)

First Aid
Signs and Symptoms of Acute Toluene 2,4-Diisocyanate Exposure: Signs and symptoms of acute exposure to toluene 2,4-diisocyanate may be severe and include burning of the skin, eyes, nose, and throat. Cough, laryngitis, chest pain, tightness of the chest, bronchitis, asthma, emphysema, and enlargement of the right side of the heart may also occur. Gastrointestinal effects may include vomiting, diarrhea, and abdominal pain. Headache, insomnia, euphoria, depression, anxiety, paranoia, neuroses, and ataxia (incoordination) may also be noted.

Emergency Life-Support Procedures: Acute exposure to toluene 2,4-diisocyanate may require decontamination and life support for the victims. Emergency personnel should wear protective clothing appropriate to the type and degree of contamination. Air-purifying or supplied-air respiratory equipment should also be worn, as necessary. Rescue vehicles should carry supplies such as plastic sheeting and disposable plastic bags to assist in preventing spread of contamination.

Inhalation Exposure:
1. Move victims to fresh air. Emergency personnel should avoid self-exposure to toluene 2,4-diisocyanate.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. RUSH to a health care facility.

Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self- exposure to toluene 2,4-diisocyanate.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Remove contaminated clothing as soon as possible.
4. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.
5. Wash exposed skin areas THOROUGHLY with soap and water.
6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
7. RUSH to a health care facility.

Ingestion Exposure:
1. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
2. DO NOT induce vomiting or attempt to neutralize!
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. Give the victims water or milk: children up to 1 year old, 125 mL (4 oz or 1/2 cup); children 1 to 12 years old, 200 mL (6 oz or 3/4 cup); adults, 250 mL (8 oz or 1 cup). Water or milk should be given only if victims are conscious and alert.
5. Activated charcoal may be administered if victims are conscious and alert. Use 15 to 30 g (1/2 to 1 oz) for children, 50 to 100 g (1-3/4 to 3-1/2 oz) for adults, with 125 to 250 mL (1/2 to 1 cup) of water.
6. Promote excretion by administering a saline cathartic or sorbitol to conscious and alert victims. Children require 15 to 30 g (1/2 to 1 oz) of cathartic; 50 to 100 g (1-3/4 to 3-1/2 oz) is recommended for adults.
7. RUSH to a health care facility. (EPA, 1998)

Physical Properties

Chemical Formula:
  • C9H6N2O2
Flash Point: 270°F (EPA, 1998)
Lower Explosive Limit (LEL): 0.9 % (EPA, 1998)
Upper Explosive Limit (UEL): 9.5 % (EPA, 1998)
Autoignition Temperature: greater than 300°F (USCG, 1999)
Melting Point: 67.1 to 70.7°F (EPA, 1998)
Vapor Pressure: 1 mmHg at 176°F (EPA, 1998)
Vapor Density (Relative to Air): 6 (EPA, 1998) - Heavier than air; will sink
Specific Gravity: 1.2244 at 68°F (EPA, 1998) - Denser than water; will sink
Boiling Point: 484°F at 760 mmHg (EPA, 1998)
Molecular Weight: 174.15 (EPA, 1998)
Water Solubility: Decomposes (NTP, 1992)
Ionization Energy/Potential: data unavailable
IDLH: 2.5 ppm ; A potential occupational carcinogen. (NIOSH, 2023)

AEGLs (Acute Exposure Guideline Levels)

Final AEGLs for 2,4-Toluene Diisocyanate (584-84-9)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 0.02 ppm 0.24 ppm 0.65 ppm
30 minutes 0.02 ppm 0.17 ppm 0.65 ppm
60 minutes 0.02 ppm 0.083 ppm 0.51 ppm
4 hours 0.01 ppm 0.021 ppm 0.32 ppm
8 hours 0.01 ppm 0.021 ppm 0.16 ppm
(NAC/NRC, 2023)

ERPGs (Emergency Response Planning Guidelines)

Chemical ERPG-1 ERPG-2 ERPG-3
TDI (Toluene 2,4- (2,6-) Diisocyanate) (584-84-9), (91-08-7) 0.01 ppm star-in-circle icon indicates that odor should be detectable near ERPG-1. 0.15 ppm 0.6 ppm
star-in-circle icon indicates that odor should be detectable near ERPG-1.
(AIHA, 2022)

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Toluene-2,4-diisocyanate; (TDI) (584-84-9) 0.02 ppm 0.083 ppm 0.51 ppm LEL = 9000 ppm
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Benzene, 2,4-diisocyanato-1-methyl- 584-84-9 500 pounds 100 pounds 100 pounds X 10000 pounds
Toluene-2,4-diisocyanate 584-84-9 500 pounds 100 pounds 100 pounds 313 10000 pounds

(EPA List of Lists, 2022)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names