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Phosgene (CG): Lung Damaging Agent

CAS #:
75-44-5

RTECS #: SY560000

UN #: 1076 (Guide 125)

Common Names:

  • Carbonic dichloride
  • Carbonyl chloride
  • Chloroformyl chloride

Agent Characteristics

Colorless gas above 47°F (8.2°C). Fog-like when concentrated. Colorless, fuming liquid below 47°F (8.2°C). May have the appearance of a white cloud. Light yellow liquid when refrigerated or compressed.

Phosgene (CG) was originally synthesized in 1812. It was used during WWI by the German army, and has since become part of the chemical arsenal of many countries including the United States. Small amounts of phosgene (CG) exist naturally in the atmosphere from the breakdown of chlorinated compounds. Phosgene is used in the preparation and manufacture of many organic chemicals especially in the dye, pharmaceutical, herbicide, insecticide, metal ore extraction, synthetic foam, resin, polymer, and chlorinating agent industries. Phosgene (CG) may also be released from household paint removers and degreasers when they are used in the presence of heat. Phosgene (CG) is shipped as a liquefied compressed gas in steel cylinders. At low concentrations, phosgene (CG) smells like newly mown hay or green corn. At high concentrations, phosgene (CG) has a strong, suffocating, unpleasant odor. However, the odor is only detectable for a short amount of time when phosgene (CG) is initially released and should not be depended on as a reliable indicator of overexposure.

  • Indoor Air: Phosgene (CG) can be released into indoor air as a gas.
  • Water: Phosgene is unlikely to contaminate water because it breaks down rapidly upon contact with water to produce hydrochloric acid and carbon dioxide.
  • Food: Phosgene is unlikely to contaminate food because it breaks down rapidly upon contact with water to produce hydrochloric acid and carbon dioxide.
  • Outdoor Air: Phosgene (CG) can be released into outdoor air as a gas.
  • Agricultural: If phosgene (CG) is released as a gas, it is highly unlikely to contaminate agricultural products.

Inhalation is the primary route of exposure to phosgene (CG). Ingestion is unlikely, as phosgene (CG) is a gas at room temperature. Exposure to phosgene (CG) may be irritating to the eyes and skin.


Personal Protective Equipment

First Responders should use a NIOSH-certified Chemical, Biological, Radiological, Nuclear (CBRN) Self Contained Breathing Apparatus (SCBA) with a Level A protective suit when entering an area with an unknown contaminant or when entering an area where the concentration of the contaminant is unknown. Level A protection should be used until monitoring results confirm the contaminant and the concentration of the contaminant.
NOTE: Safe use of protective clothing and equipment requires specific skills developed through training and experience.

Select when the greatest level of skin, respiratory, and eye protection is required. This is the maximum protection for workers in danger of exposure to unknown chemical hazards or levels above the IDLH or greater than the AEGL-2.

  • A NIOSH-certified CBRN full-face-piece SCBA operated in a pressure-demand mode or a pressure-demand supplied air hose respirator with an auxiliary escape bottle.
  • A Totally-Encapsulating Chemical Protective (TECP) suit that provides protection against CBRN agents.
  • Chemical-resistant gloves (outer).
  • Chemical-resistant gloves (inner).
  • Chemical-resistant boots with a steel toe and shank.
  • Coveralls, long underwear, and a hard hat worn under the TECP suit are optional items.

Select when the highest level of respiratory protection is necessary but a lesser level of skin protection is required. This is the minimum protection for workers in danger of exposure to unknown chemical hazards or levels above the IDLH or greater than AEGL-2. It differs from Level A in that it incorporates a non-encapsulating, splash-protective, chemical-resistant splash suit that provides Level A protection against liquids but is not airtight.

  • A NIOSH-certified CBRN full-face-piece SCBA operated in a pressure-demand mode or a pressure-demand supplied air hose respirator with an auxiliary escape bottle.
  • A hooded chemical-resistant suit that provides protection against CBRN agents.
  • Chemical-resistant gloves (outer).
  • Chemical-resistant gloves (inner).
  • Chemical-resistant boots with a steel toe and shank.
  • Coveralls, long underwear, a hard hat worn under the chemical-resistant suit, and chemical-resistant disposable boot-covers worn over the chemical-resistant suit are optional items.

Select when the contaminant and concentration of the contaminant are known and the respiratory protection criteria factors for using Air Purifying Respirators (APR) or Powered Air Purifying Respirators (PAPR) are met. This level is appropriate when decontaminating patient/victims.

  • A NIOSH-certified CBRN tight-fitting APR with a canister-type gas mask or CBRN PAPR for air levels greater than AEGL-2.
  • A NIOSH-certified CBRN PAPR with a loose-fitting face-piece, hood, or helmet and a filter or a combination organic vapor, acid gas, and particulate cartridge/filter combination or a continuous flow respirator for air levels greater than AEGL-1.
  • A hooded chemical-resistant suit that provides protection against CBRN agents.
  • Chemical-resistant gloves (outer).
  • Chemical-resistant gloves (inner).
  • Chemical-resistant boots with a steel toe and shank.
  • Escape mask, face shield, coveralls, long underwear, a hard hat worn under the chemical-resistant suit, and chemical-resistant disposable boot-covers worn over the chemical-resistant suit are optional items.

Select when the contaminant and concentration of the contaminant are known and the concentration is below the appropriate occupational exposure limit or less than AEGL-1 for the stated duration times.

  • Limited to coveralls or other work clothes, boots, and gloves.

Emergency Response

  • Phosgene (CG) reacts violently with strong oxidants, amines, alkalis, and many metals.
  • Phosgene (CG) reacts with alcohols and ammonia.
  • Above 572°F (300°C), phosgene (CG) decomposes in the presence of moisture to form hydrochloric acid and carbon dioxide.
  • In the presence of moisture, phosgene (CG) attacks plastic, rubber, and many metals.
  • Phosgene is not combustible.
  • Containers may explode when heated.
  • Ruptured cylinders may rocket.
  • Phosgene (CG) is non-combustible.
  • When heated to decomposition, phosgene (CG) produces toxic and corrosive fumes (hydrogen chloride, carbon monoxide, and chlorine).
  • For small fires, use dry chemical or carbon dioxide.
  • For large fires, use water spray, fog, or regular foam. Move containers from the fire area if it is possible to do so without risk to personnel. Do not get water inside containers. Damaged cylinders should be handled only by specialists.
  • For fire involving tanks, fight the fire from maximum distance or use unmanned hose holders or monitor nozzles. Cool containers with flooding quantities of water until well after the fire is out. Do not direct water at the source of the leak or at safety devices; icing may occur. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tanks. Always stay away from tanks engulfed in fire.
  • Run-off from fire control may cause pollution.
  • If the situation allows, control and properly dispose of run-off (effluent).
  • If a tank, rail car, or tank truck is involved in a fire, isolate it for 1 mi (1600 m) in all directions; also consider initial evacuation for 1 mi (1600 m) in all directions.
  • Small spills (involving the release of approximately 52.83 gallons (200 liters) or less)
  • First isolate in all directions 500 ft (150 m).
  • Then protect persons downwind during the day: 0.8 mi (1.3 km).
  • Then protect persons downwind during the night: 2.0 mi (3.3 km).
  • Large spills (involving quantities greater than 52.83 gallons (200 liters))
  • First isolate in all directions 2500 ft (800 m).
  • Then protect persons downwind during the day: 4.5 mi (7.3 km).
  • Then protect persons downwind during the night: 7.0+ mi (11.0+ km).
  • Vapors are heavier than air. They will spread along the ground and collect and stay in poorly-ventilated, low-lying, or confined areas (e.g., sewers, basements, and tanks).
  • Hazardous concentrations may develop quickly in enclosed, poorly-ventilated, or low-lying areas. Keep out of these areas. Stay upwind.
  • Phosgene (CG) liquid sinks in water.
  • Health: 4
  • Flammability: 0
  • Reactivity: 1
  • Special:

Health: 4, Flammability: 0, Reactivity: 1, Special:

  • OSHA: 61
  • NIOSH: Not established/determined
References are provided for the convenience of the reader and do not imply endorsement by NIOSH.
  • AIR MATRIX
    Adler J, Doering HR [1990]. Detection of phosgene and hydrogen cyanide by means of ion-mobility spectrometry. ZfI-Mitt 154:97-111.Bächmann K, Polzer J [1989]. Determination of tropospheric phosgene and other halocarbons by capillary gas chromatography. J Chromatogr A 481:373-379.Dangwal SK [1994]. A spectrophotometric method for determination of phosgene in air. Ind Health 32(1):41-47.

    Hendershott JP [1986]. The simultaneous determination of chloroformates and phosgene at low concentrations in air using a solid sorbent sampling gas-chromatographic procedure. AIHA J 47(12):742-746.

    Massil SE, Ovadia D [1991].Determination of phosgene as its N,N,N’,N’-tetraethylurea derivative by gas chromatography. J Chromatogr A 538(2):435-440.

    Matz G, Hunte T, Rusch, P, Harder A, Schillings A, Rechenbach P, Harig R, Schroeder W [2002]. New techniques for rapid analysis of hazardous materials at chemical accidents and fires. Part 1. Gas detector array for detection and warning. Gefahrstoffe—Reinhaltung der Luft 62(5):203-207.

    Nakano N, Yamamoto A, Kobayashi Y, Nagashima K [1995]. Development of a monitoring tape for phosgene in air. Talanta 42(4)641-645.

    Rando RJ, Poovey HG, Chang SN [1993]. Collection and chemical derivatization of airborne phosgene with 1-(2-pyridyl)-piperazine and determination by high-performance liquid-chromatography. J Liq Chromatogr 16(15):3291-3309.

    Schoene K, Bruckert HJ, Steinhanses J [1993]. Derivatization of acylating gases and vapours on the sorbent tube and gas-chromatographic analysis of the products by atomic-emission and mass-spectrometric detection. Fresenius’ J Anal Chem 345(11):688-694.

    Wu WS, Gaind VS [1993]. Determination of phosgene (carbonyl chloride) in air by high-performance liquid-chromatography with a dual selective detection system. Anal 118(10):1285-1287.

  • OTHER
    No references were identified for this sampling matrix for this agent.
  • SOIL MATRIX
    No references were identified for this sampling matrix for this agent.
  • SURFACES
    No references were identified for this sampling matrix for this agent.
  • WATER
    No references were identified for this sampling matrix for this agent.

Signs/Symptoms

Patient/victims exposed to low concentrations of phosgene (CG) vapor may not experience any irritation, or they may have only mild irritation of the upper airways; this allows them to inhale phosgene (CG) for a longer time and more deeply into the lungs. There is a symptom-free (latent) period of 30 minutes to 72 hours, depending on the severity of exposure. The more severe the exposure, the shorter the latency. Physical exertion may bring on shortness of breath or difficulty breathing (dyspnea) or fluid accumulation in the lungs (pulmonary edema). Onset of pulmonary edema within 2 to 6 hours is predictive of severe injury. If the patient/victim survives the initial 48 hours after exposure, recovery is likely.

Phosgene (CG) exerts its toxicity by its action on the body’s proteins, as well as through the production of hydrochloric acid. The lung is the major target organ. Irritation of the eyes and upper respiratory tract may be mild, while effects on the cells of the lower airways and lungs may be severe. Heart failure and death may occur as a complication of lung damage.

  • Gas (high concentrations): Tear production (lacrimation), accumulation of blood (hyperemia), inflammation, and clouding (opacification) of the cornea.
  • Liquid: Clouding (opacification) of the cornea and delayed perforation.
  • Phosgene (CG) is present as a gas at room temperature, so ingestion is unlikely.
  • Mild: No adverse health effects or only mild upper airway irritation; effects may improve when the patient/victim is removed from exposure; more severe adverse health effects are possible after a delay (latent period).
  • Mild to moderate: After a symptom-free interval (latent period), irritation of the upper airway, dryness and burning of the throat, painful cough, choking, sense of chest discomfort, difficulty breathing or shortness of breath (dyspnea), spasmodic narrowing of the large airways (bronchospasm), and possible nausea and vomiting (emesis) may occur. Patient/victims with underlying reactive airways or asthma may be at increased risk.
  • Severe: Rapid accumulation of fluid in the lungs (pulmonary edema); shallow rapid respirations; severe, painful coughing fits producing frothy liquid (sputum); possible upper airway closure (laryngospasm) that may result in sudden death; difficulty breathing or shortness of breath (dyspnea); possible cardiovascular collapse due to low blood oxygen; and low blood pressure secondary to fluid accumulation in the lungs (pulmonary edema).
  • Gas: Irritation and redness (erythema) on contact with wet or moist skin.
  • Severe skin burns or frostbite may occur as a result of contact with compressed liquefied gas.

Decontamination

The purpose of decontamination is to make an individual and/or their equipment safe by physically removing toxic substances quickly and effectively. Care should be taken during decontamination, because absorbed agent can be released from clothing and skin as a gas. Your Incident Commander will provide you with decontaminants specific for the agent released or the agent believed to have been released.

The following are recommendations to protect the first responders from the release area:

  • Position the decontamination corridor upwind and uphill of the hot zone. The warm zone should include two decontamination corridors. One decontamination corridor is used to enter the warm zone and the other for exiting the warm zone into the cold zone. The decontamination zone for exiting should be upwind and uphill from the zone used to enter.
  • Decontamination area workers should wear appropriate PPE. See the PPE section of this card for detailed information.
  • A solution of detergent and water (which should have a pH value of at least 8 but should not exceed a pH value of 10.5) should be available for use in decontamination procedures. Soft brushes should be available to remove contamination from the PPE. Labeled, durable 6-mil polyethylene bags should be available for disposal of contaminated PPE.

The following methods can be used to decontaminate an individual:

  • Decontamination of First Responder:
    • Begin washing PPE of the first responder using soap and water solution and a soft brush. Always move in a downward motion (from head to toe). Make sure to get into all areas, especially folds in the clothing. Wash and rinse (using cold or warm water) until the contaminant is thoroughly removed.
    • Remove PPE by rolling downward (from head to toe) and avoid pulling PPE off over the head. Remove the SCBA after other PPE has been removed.
    • Place all PPE in labeled durable 6-mil polyethylene bags.
  • Decontamination of Patient/Victim:
    • Remove the patient/victim from the contaminated area and into the decontamination corridor.
    • Remove all clothing (at least down to their undergarments) and place the clothing in a labeled durable 6-mil polyethylene bag.
    • Thoroughly wash and rinse (using cold or warm water) the contaminated skin of the patient/victim using a soap and water solution. Be careful not to break the patient/victim’s skin during the decontamination process, and cover all open wounds.
    • Cover the patient/victim to prevent shock and loss of body heat.
    • Move the patient/victim to an area where emergency medical treatment can be provided.

First Aid

Initial treatment is primarily supportive. The patient/victim should be kept warm and quiet. Physical exertion should be avoided during treatment and recovery.

There is no antidote for phosgene (CG) toxicity.

  • Immediately remove the patient/victim from the source of exposure.
  • Immediately wash eyes with large amounts of tepid water for at least 15 minutes.
  • Eye exposure is unlikely to occur without inhalation exposure.
  • See Inhalation.
  • Seek medical attention immediately.
  • Not established/determined
  • Immediately remove the patient/victim from the source of exposure.
  • Ensure that the patient/victim has an unobstructed airway.
  • Evaluate respiratory function and pulse. If shortness of breath, difficulty breathing, or respiratory distress occur, administer oxygen.
  • Assist ventilation as required. Always use a barrier or bag-valve-mask device.
  • Monitor the patient/victim for signs of accumulation of fluid in the lungs (pulmonary edema), such as difficulty breathing or shortness of breath (dyspnea) and chest tightness.
  • Monitor for and treat spasmodic narrowing of airways.
  • Monitor the patient/victim for signs of whole-body (systemic) effects and administer symptomatic treatment as necessary.
  • Keep the patient/victim calm and avoid unnecessary exertion or movement.
  • Seek medical attention immediately.
  • Immediately remove the patient/victim from the source of exposure.
  • See the Decontamination section for patient/victim decontamination procedures.
  • Monitor the patient/victim for signs of whole-body (systemic) effects.
  • If signs of whole-body (systemic) poisoning appear, see Inhalation for treatment recommendations.
  • In case of frostbite, protect the injured area from further injury until sustained re-warming can be initiated.
  • Seek medical attention immediately.

Long-Term Implications

It has been recommended that patient/victims be monitored for 12 to 48 hours for potential accumulation of fluid in the lungs (pulmonary edema). However, symptoms may be delayed for up to 72 hours. If a patient/victim survives the first 48 hours after exposure, recovery is more likely.

Patient/victims who develop and recover from symptomatic phosgene inhalation are at increased risk for chronic lung damage, increased susceptibility to lung infections, reactive airway dysfunction syndrome (RADS), and an increased risk for sensitivity to airborne irritants.

Information is unavailable about the carcinogenicity, developmental toxicity, or reproductive toxicity from chronic or repeated exposure to phosgene (CG). Workers exposed to phosgene (CG) over time (i.e., chronically) experienced an increased rate of adverse health effects and death due to inflammation of the lung and airways, destruction of lung tissue (emphysema), and loss of normal lung function. Chronic low level exposure to phosgene (CG) may cause chronic inflammation and/or infection of the lungs, which may improve with time or may progress to the accumulation of fluid in the lungs (pulmonary edema).


On-Site Fatalities

  • Consult with the Incident Commander regarding the agent dispersed, dissemination method, level of PPE required, location, geographic complications (if any), and the approximate number of remains.
  • Coordinate responsibilities and prepare to enter the scene as part of the evaluation team along with the FBI HazMat Technician, local law enforcement evidence technician, and other relevant personnel.
  • Begin tracking remains using waterproof tags.
  • Wear PPE until all remains are deemed free of contamination.
  • Establish a preliminary (holding) morgue.
  • Gather evidence, and place it in a clearly labeled impervious container. Hand any evidence over to the FBI.
  • Remove and tag personal effects.
  • Perform a thorough external evaluation and a preliminary identification check.
  • See the Decontamination section for decontamination procedures.
  • Decontaminate remains before they are removed from the incident site.
See Guidelines for Mass Fatality Management During Terrorist Incidents Involving Chemical Agents, U.S. Army Soldier and Biological Chemical Command (SBCCOM), November, 2001 for detailed recommendations.

Occupational Exposure Limits

  • NIOSH REL:
    • TWA (10-hour): 0.1 ppm (0.4 mg/m3)
    • Ceiling (15-minute): 0.2 ppm (0.8 mg/m3)
  • OSHA PEL:
    • TWA (8-hour): 0.1 ppm (0.4 mg/m3)
    • Note: The odor threshold for phosgene (CG) is 5X higher than the OSHA PEL.
  • ACGIH TLV:
    • TWA (8-hour): 0.1 ppm
  • NIOSH IDLH: 2 ppm
  • DOE TEEL:
    • TEEL-0: 0.4 mg/m3
    • TEEL-1: 0.4 mg/m3
    • TEEL-2: 1.21 mg/m3
    • TEEL-3: 3.03 mg/m3
  • AIHA ERPG:
    • ERPG-1: Not appropriate.
    • ERPG-2: 0.2 ppm
    • ERPG-3: 1 ppm

Acute Exposure Guidelines

Acute Exposure Guidelines
10 min 30 min 60 min 4 hr 8 hr
AEGL 1
(discomfort, non-disabling) – ppm
NR NR NR NR NR
AEGL 2
(irreversible or other serious, long-lasting effects or impaired ability to escape) – ppm
0.60 ppm 0.60 ppm 0.30 ppm 0.080 ppm 0.040 ppm
AEGL 3
(life-threatening effects or death) – ppm
3.6 ppm 1.5 ppm 0.75 ppm 0.20 ppm 0.090 ppm

NR = Not recommended due to insufficient data

Technical Support Document


Decontamination (Environment and Equipment)

The following methods can be used to decontaminate the environment/spillage disposal:

  • Do not touch or walk through the spilled agent if at all possible. However, if you must, personnel should wear the appropriate PPE during environmental decontamination. See the PPE section of this card for detailed information.
  • Keep combustibles (e.g., wood, paper, and oil) away from the spilled agent. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact the spilled agent.
  • Do not direct water at the spill or the source of the leak.
  • Stop the leak if it is possible to do so without risk to personnel, and turn leaking containers so that gas rather than liquid escapes.
  • Prevent entry into waterways, sewers, basements, or confined areas.
  • Isolate the area until gas has dispersed.
  • Ventilate the area.

Agents can seep into the crevices of equipment making it dangerous to handle. The following methods can be used to decontaminate equipment:

  • Not established/determined

Agent Properties

  • Chemical Formula:
    CCl2O
  • Aqueous solubility:
    Soluble
  • Boiling Point:
    47°F (8.2°C)
  • Density:
    Gas: 3.48 (air = 1)
    Liquid: 1.432 at 108°F (40°C)
  • Flammability:
    Nonflammable
  • Flashpoint:
    Not flammable
  • Ionization potential:

    11.55 eV

  • Log Kbenzene-water:
    Not established/determined
  • Log Kow (estimated):
    -0.71
  • Melting Point:
    -180°F (-118°C)
  • Molecular Mass:
    98.92
  • Soluble In:

    Freely soluble in benzene, toluene, glacial acetic acid, and most liquid hydrocarbons; soluble in carbon tetrachloride and chloroform.

  • Specific Gravity:
    Liquid: 1.43 at 32°F (0°C)
  • Vapor Pressure:
    1,215 mm Hg at 68°F (20°C)
  • Volatility:
    2,200,000 mg/m3 at 14°F (-10°C)
    4,300,000 mg/m3 at 46°F (7.6°C)
    528,000 mg/m3 at -40°F (-40°C)

Hazardous Materials Warning Labels/Placards

  • Shipping Name:
    Phosgene
  • Identification Number:
    1076 (Guide 125)
  • Hazardous Class or Division:
    2.3
  • Subsidiary Hazardous Class or Division:
    8
  • Label:
    Poison (Toxic) Inhalation Hazard
    Corrosive
  • Placard Image:
    dot_class3_poisoninhalhazard dot_class8_corrosive

Trade Names and Other Synonyms

  • Carbonic dichloride
  • Carbon dichloride oxide
  • Carbon oxychloride
  • Carbone (oxychlorure de) (French)
  • Carbonic acid dichloride
  • Carbonic chloride
  • Carbonio (ossicloruro di) (Italian)
  • Carbonyl dichloride
  • Carbonylchlorid (German)
  • Combat gas
  • Diphosgene
  • D-Stoff
  • Fosgeen (Dutch)
  • Fosgen (Polish)
  • Fosgene (Italian)
  • Green cross
  • Koolstofoxychloride (Dutch)
  • Phosgen (German)
Who to Contact in an Emergency

In the event of a poison emergency, call the poison center immediately at 1-800-222-1222. If the person who is poisoned cannot wake up, has a hard time breathing, or has convulsions, call 911 emergency services.

For information on who to contact in an emergency, see the CDC website at emergency.cdc.gov or call the CDC public response hotline at (888) 246-2675 (English), (888) 246-2857 (Español), or (866) 874-2646 (TTY).

Important Notice

The user should verify compliance of the cards with the relevant STATE or TERRITORY legislation before use. NIOSH, CDC 2003.