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Chemical Datasheet

DICHLOROFLUOROMETHANE

2.2 - Non-flammable, non-poisonous gas

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 75-43-4   (DICHLOROFLUOROMETHANE)
  • 1029
  • Non-Flammable Gas
  • DFM
NIOSH Pocket Guide International Chem Safety Card
Dichloromonofluoromethane
  • DICHLOROMONOFLUOROMETHANE
NFPA 704
data unavailable
General Description
Dichlorofluoromethane is a colorless, odorless gas. It is shipped as a liquid under its own vapor pressure. Contact with the liquid may cause frostbite to unprotected skin. It can asphyxiate by displacement of air. Exposure of the container to prolonged heat or fire may cause it to rupture violently and rocket.

Hazards

Reactivity Alerts
none
Air & Water Reactions
Slightly soluble in water.
Fire Hazard
Special Hazards of Combustion Products: Toxic fumes of chlorine and fluorine may be produced in fire. (USCG, 1999)
Health Hazard
INHALATION: May cause giddiness, light-headedness, disorientation, nausea, vomiting, narcosis, cardiac dysrhythmias, hypotension, and death. SKIN: May cause frostbite or irritation. EYES: May cause irritation or cold injury. (USCG, 1999)
Reactivity Profile
DICHLOROFLUOROMETHANE is incompatible with the following: Chemically-active metals such as sodium, potassium, calcium, powdered aluminum, zinc & magnesium; acid; acid fumes (NIOSH, 2022).
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 Dichloromonofluoromethane:

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
Excerpt from NIOSH Pocket Guide for Dichloromonofluoromethane:

Eye: FROSTBITE - If eye tissue is frozen, seek medical attention immediately; if tissue is not frozen, immediately and thoroughly flush the eyes with large amounts of water for at least 15 minutes, occasionally lifting the lower and upper eyelids. If irritation, pain, swelling, lacrimation, or photophobia persist, get medical attention as soon as possible.

Skin: FROSTBITE - If frostbite has occurred, seek medical attention immediately; do NOT rub the affected areas or flush them with water. In order to prevent further tissue damage, do NOT attempt to remove frozen clothing from frostbitten areas. If frostbite has NOT occurred, immediately and thoroughly wash contaminated skin with soap and water.

Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible. (NIOSH, 2023)

Physical Properties

Chemical Formula:
  • CHCl2F
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: 1022°F (USCG, 1999)
Melting Point: -211°F (USCG, 1999)
Vapor Pressure: 2217.93 mmHg (USCG, 1999)
Vapor Density (Relative to Air): 3.57 (NIOSH, 2023) - Heavier than air; will sink
Specific Gravity: 1.48 at 68°F (USCG, 1999) - Denser than water; will sink
Boiling Point: 48°F at 760 mmHg (USCG, 1999)
Molecular Weight: 102.92 (USCG, 1999)
Water Solubility: 0.7 % at 86°F (NIOSH, 2023)
Ionization Energy/Potential: 12.39 eV (NIOSH, 2023)
IDLH: 5000 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
Dichlorofluoromethane; (Freon 21, CFC 21) (75-43-4) 30 ppm 8300 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
Dichlorofluoromethane 75-43-4 313
HCFC-21 75-43-4 X

(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