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Chemical Datasheet

DICHLORODIFLUOROMETHANE

2.2 - Non-flammable, non-poisonous gas

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 75-71-8   (DICHLORODIFLUOROMETHANE)
  • 1028
  • Non-Flammable Gas
  • DCF
NIOSH Pocket Guide International Chem Safety Card
Dichlorodifluoromethane
  • DICHLORODIFLUOROMETHANE
NFPA 704
data unavailable
General Description
A colorless gas having a faint ethereal odor. Shipped as a liquid confined under its own vapor pressure. Contact with the unconfined liquid can cause frostbite. Both components are noncombustible. Can asphyxiate by the displacement of air. Exposure of the closed container to prolonged heat or fire can cause it to rupture violently and rocket.

Hazards

Reactivity Alerts
none
Air & Water Reactions
The liquefied gas poured into water can be violently explosive. This is due to the phase transition from superheated liquid to vapor.
Fire Hazard
Special Hazards of Combustion Products: Although nonflammable, dissociation products generated in a fire may be irritating or toxic.

Behavior in Fire: Helps extinguish fire. (USCG, 1999)
Health Hazard
INHALATION: some narcosis when 10% in air is breathed. (USCG, 1999)
Reactivity Profile
The reaction of aluminum with various halogenated hydrocarbons produces a self-sustaining reaction with sufficient heat to melt aluminum pieces, examples of other halogenated hydrocarbons are fluorotrichloromethane, dichlorodifluoromethane, chlorodifluoromethane, tetrafluoromethane. The vigor of the reaction appears to be dependent on the combined degree of fluorination and the vapor pressure, [Chem. Eng. News 39(27):44(1961)].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
Excerpt from 126 Polymerizable warning [Gases - Compressed or Liquefied (Including Refrigerant Gases)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 100 meters (330 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 500 meters (1/3 mile).

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
Excerpt from 126 Polymerizable warning [Gases - Compressed or Liquefied (Including Refrigerant Gases)]:

Use extinguishing agent suitable for type of surrounding fire.

SMALL FIRE: Dry chemical or CO2.

LARGE FIRE: Water spray, fog or regular foam. If it can be done safely, move undamaged containers away from the area around the fire. Damaged cylinders should be handled only by specialists.

FIRE INVOLVING TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Do not direct water at source of leak or safety devices; icing may occur. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. Some of these materials, if spilled, may evaporate leaving a flammable residue. (ERG, 2020)
Non-Fire Response
Excerpt from 126 Polymerizable warning [Gases - Compressed or Liquefied (Including Refrigerant Gases)]:

Do not touch or walk through spilled material. Stop leak if you can do it without risk. Do not direct water at spill or source of leak. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. If possible, turn leaking containers so that gas escapes rather than liquid. Prevent entry into waterways, sewers, basements or confined areas. Allow substance to evaporate. Ventilate the area. (ERG, 2020)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Dichlorodifluoromethane:

Skin: FROSTBITE - Compressed gases may create low temperatures when they expand rapidly. Leaks and uses that allow rapid expansion may cause a frostbite hazard. Wear appropriate personal protective clothing to prevent the skin from becoming frozen.

Eyes: FROSTBITE - Wear appropriate eye protection to prevent eye contact with the liquid that could result in burns or tissue damage from frostbite.

Wash skin: No recommendation is made specifying the need for washing the substance from the skin (either immediately or at the end of the work shift).

Remove: No recommendation is made specifying the need for removing clothing that becomes wet or contaminated.

Change: No recommendation is made specifying the need for the worker to change clothing after the workshift.

Provide: FROSTBITE WASH - Quick drench facilities and/or eyewash fountains should be provided within the immediate work area for emergency use where there is any possibility of exposure to liquids that are extremely cold or rapidly evaporating. (NIOSH, 2023)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. If symptoms (such as redness or irritation) develop, immediately transport the victim to a hospital.

SKIN: CAUTION: Exposure of skin to compressed gases may result in freezing of the skin. Treatment for frostbite may be necessary. Remove the victim from the source of contamination. IMMEDIATELY wash affected areas gently with COLD water (and soap, if necessary) while removing and isolating all contaminated clothing. Dry carefully with clean, soft towels. If symptoms such as inflammation or irritation develop, IMMEDIATELY call a physician or go to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: This compound is a gas, therefore inhalation is the first route of exposure. (NTP, 1992)

Physical Properties

Chemical Formula:
  • CCl2F2
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: Not flammable (USCG, 1999)
Melting Point: -252°F (NTP, 1992)
Vapor Pressure: 5 atm at 61°F (NTP, 1992)
Vapor Density (Relative to Air): 4.2 (NIOSH, 2023) - Heavier than air; will sink
Specific Gravity: 1.35 at 59°F (USCG, 1999) - Denser than water; will sink
Boiling Point: -21.6°F at 760 mmHg (NTP, 1992)
Molecular Weight: 120.91 (NTP, 1992)
Water Solubility: Insoluble (NTP, 1992)
Ionization Energy/Potential: 11.75 eV (NIOSH, 2023)
IDLH: 15000 ppm (NIOSH, 2023)

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Dichlorodifluoromethane; (Freon 12, CFC 12) (75-71-8) 3000 ppm 10000 ppm 50000 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
CFC-12 75-71-8 5000 pounds X U075
Dichlorodifluoromethane 75-71-8 5000 pounds 313 U075

(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