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Chemical Datasheet


2.3 - Poisonous gas 5.1 - Oxidizer 8 - Corrosive

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7790-91-2   (CHLORINE TRIFLUORIDE)
  • Poison Gas
  • Oxidizer
  • Corrosive
NFPA 704
Diamond Hazard Value Description
4 3
W ox
Blue Health 4 Can be lethal.
Red Flammability 0 Will not burn under typical fire conditions.
Yellow Instability 3 Capable of detonation or explosive decomposition or explosive reaction but requires a strong initiating source or must be heated under confinement before initiation.
White Special W
Reacts violently or explosively with water.
Possesses oxidizing properties.
(NFPA, 2010)
NIOSH Pocket Guide International Chem Safety Card
Chlorine trifluorideexternal link
General Description
A colorless gas or green liquid with a pungent odor. Boils at 53°F. It reacts with water to form chlorine and hydrofluoric acid with release of heat. Contact with organic materials may result in spontaneous ignition. It is corrosive to metals and tissue. Prolonged exposure to low concentrations or short term exposure to high concentrations may result in adverse health effects. Under prolonged exposure to fire or intense heat the container may violently rupture and rocket.


Reactivity Alerts
Air & Water Reactions
A violent reaction occurs with water or ice generating acidic HF and chlorine, [Sidgwick, 1156(1950)]. The release of Chlorine Trifluoride to the atmosphere rapidly generates two toxic reaction products: HF and Chlorine Dioxide, [Lombardi, D.A. and M.D. Cheng 1996. "Modeling Accidental Releases of Chlorine Trifluoride to the Atmosphere," Paper No. 96-WP66B.02, presented at the 89th Annual Meeting of the Air and Waste Management Association, Nashville, Tennessee, June 23-26].
Fire Hazard
Special Hazards of Combustion Products: If released from container, fumes are toxic and irritating.

Behavior in Fire: If released from container, can increase the intensity of fire. Containers may explode. (USCG, 1999)
Health Hazard
Inhalation causes extreme irritation of respiratory tract; pulmonary edema may result. Vapors are very irritating to eyes and skin; liquid causes severe burns. (USCG, 1999)
Reactivity Profile
CHLORINE TRIFLUORIDE is a low-boiling liquid (b.p. 12° C) which is irritating and toxic in the gaseous state. A highly reactive oxidant, it is spontaneously flammable and used as a rocket propellant. It is incompatible with fuels and nitro compounds. Interaction with water is violent and may be explosive, even with ice [Sidgwick, 1950, p. 1156]. It undergoes an immediate explosive reaction on contact with hydrocarbons or halocarbons even at -70° C [Brower, K. R., J. Fluorine Chem., 1986, 31, p. 333]. Solutions with carbon tetrachloride are capable of detonation, while solutions with nitroaryl compounds (TNT, hexanitrobiphenyl) or highly chlorinated compounds are extremely shock-sensitive. Violent, sometimes explosive reaction with hydrogen containing materials, e.g., acetic acid, ammonia, benzene, ether, coal gas, hydrogen, hydrogen sulfide, methane, or fluoroamino compounds. Ignition with fibrous materials (cotton, paper, wood). [Mellor, 1956, vol. 2, suppl. 1, p. 155]. Explosive gaseous products (chlorodifluoroamine) are formed with ammonium fluoride or ammonium hydrogen fluoride [Gardner, D. M. et al., Inorg., Chem., 1963, 2, p. 413]. Ignition occurs on contact with iodine, boron-containing materials (boron powder, tetraboron carbide, boron-aluminum), fibrous or finely divided refractory materials (asbestos, glass, wool, sand, tungsten carbide). Violent reactions occur with mineral acids (nitric acid, sulfuric acid), chromium trioxide, ruthenium metal, selenium tetrafluoride. [Bretherick, 5th ed., 1995, p. 1235]. Chlorine trifluoride is a hypergolic oxidizer and contact with a number of metals and their oxides (aluminum, antimony, arsenic, calcium, copper, iridium, iron, lithium, lead, magnesium, molybdenum, osmium, potassium, rhodium, sodium, selenium, silver, tellurium, tin, tungsten, zinc), nonmetals (phosphorus, silicon, sulfur), salts (mercury iodide, potassium iodide, silver, nitrate, potassium carbonate) will result in a violent reaction often followed by ignition [Mellor, 1956, vol. 2, suppl. 1, p. 155; Sidgwick, 1950, p. 1156].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents


Response Recommendations

Isolation and Evacuation


SPILL: See ERG Table 1 - Initial Isolation and Protective Action Distances on the UN/NA 1749 datasheet.


SMALL FIRE: CAUTION: These materials do not burn but will support combustion. Some will react violently with water. Contain fire and let burn. If fire must be fought, water spray or fog is recommended. Water only; no dry chemical, CO2 or Halon®. Do not get water inside containers. Move containers from fire area if you can do it without risk. Damaged cylinders should be handled only by specialists.

Non-Fire Response

Protective Clothing
Skin: Wear appropriate personal protective clothing to prevent skin contact.

Eyes: Wear appropriate eye protection to prevent eye contact.

Wash skin: If the chemical is in liquid form, the worker should immediately wash the skin when it becomes contaminated.

Remove: If chemical is in liquid form, work clothing that becomes wet or significantly contaminated should be removed and replaced.


Provide: Eyewash fountains should be provided (when chemical is in liquid form) in areas where there is any possibility that workers could be exposed to the substance; this is irrespective of the recommendation involving the wearing of eye protection. Facilities for quickly drenching the body should be provided (when chemical is in liquid form) 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, 2016)
DuPont Tychem® Suit Fabrics
Tychem® Fabric Legend
QC = Tychem QC
SL = Tychem SL
TF = Tychem F
TP = Tychem ThermoPro
C3 = Tychem CPF 3
BR = Tychem BR
RC = Tychem Responder® CSM
TK = Tychem TK
RF = Tychem Reflector®
Testing Details
Normalized Breakthrough Times (in Minutes)
Chlorine trifluoride 7790-91-2 Vapor 45 45 45 45

Special Warnings from DuPont


(DuPont, 2016)

First Aid

Skin: If this chemical contacts the skin, immediately flush the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water. Get medical attention promptly.


Swallow: If this chemical in liquid form has been swallowed, get medical attention immediately. (NIOSH, 2016)

Physical Properties

Chemical Formula:
  • ClF3
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: -105 ° F (USCG, 1999)
Vapor Pressure: 1.4 atm (NIOSH, 2016)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 1.85 at 51.8 ° F (USCG, 1999)
Boiling Point: 53 ° F at 760 mm Hg (USCG, 1999)
Molecular Weight: 92.5 (USCG, 1999)
Water Solubility: Reacts with water (NIOSH, 2016)
Ionization Potential: 13.00 eV (NIOSH, 2016)
IDLH: 20 ppm (NIOSH, 2016)

AEGLs (Acute Exposure Guideline Levels)

Final AEGLs for Chlorine trifluoride (7790-91-2)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 0.12 ppm 8.1 ppm 84 ppm
30 minutes 0.12 ppm 3.5 ppm 36 ppm
60 minutes 0.12 ppm 2 ppm 21 ppm
4 hours 0.12 ppm 0.7 ppm 7.3 ppm
8 hours 0.12 ppm 0.41 ppm 7.3 ppm
(NAC/NRC, 2016)

ERPGs (Emergency Response Planning Guidelines)

Chemical ERPG-1 ERPG-2 ERPG-3
Chlorine Trifluoride (7790-91-2) 0.1 ppm star-in-circle icon indicates that odor should be detectable near ERPG-1. 1 ppm 10 ppm
(AIHA, 2016)

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Chlorine trifluoride (7790-91-2) 0.12 ppm 2 ppm 21 ppm
(DOE, 2016)

Regulatory Information


EPA Consolidated List of Lists

No regulatory information available.

DHS Chemical Facility Anti-Terrorism Standards (CFATS)

Chemical of Interest CAS Number Min Conc STQ Security
Min Conc STQ Security
Min Conc STQ Security
Chlorine trifluoride 7790-91-2 9.97 % 45 pounds WME

(DHS, 2007)

Alternate Chemical Names
