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Dichloromonofluoromethane

Synonyms & Trade Names
Dichlorofluoromethane, Fluorodichloromethane, Freon® 21, Genetron® 21, Halon® 112, Refrigerant 21
CAS No.
75-43-4
RTECS No.
DOT ID & Guide
1029 126
Formula
CHCl₂F
Conversion
1 ppm = 4.21 mg/m3
IDLH
5000 ppm
See: 75434
Exposure Limits
NIOSH REL
TWA 10 ppm (40 mg/m3)
OSHA PEL
TWA 1000 ppm (4200 mg/m3) See Appendix G
Measurement Methods
NIOSH 2516
See: NMAM or OSHA Methods
Physical Description
Colorless gas with a slight, ether-like odor. [Note: A liquid below 48°F. Shipped as a liquefied compressed gas.]
Molecular Weight
102.9
Boiling Point
48°F
Freezing Point
-211°F
Solubility
(86°F): 0.7%
Vapor Pressure
(70°F): 1.6 atm
Ionization Potential
12.39 eV
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Relative Gas Density
3.57
Nonflammable Gas
Incompatibilities & Reactivities
Chemically-active metals such as sodium, potassium, calcium, powdered aluminum, zinc & magnesium; acid; acid fumes
Exposure Routes
inhalation, skin and/or eye contact (liquid)
Symptoms
asphyxia, cardiac arrhythmias, cardiac arrest; liquid: frostbite
Target Organs
respiratory system, cardiovascular system
Personal Protection/Sanitation
(See protection codes)
Skin:Frostbite
Eyes:Frostbite
Wash skin:No recommendation
Remove:No recommendation
Change:No recommendation
Provide:Frostbite wash
First Aid
(See procedures)
Eye:Frostbite
Skin:Frostbite
Breathing:Respiratory support
Respirator Recommendations

NIOSH

Up to 100 ppm:
(APF = 10) Any supplied-air respirator

Up to 250 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode

Up to 500 ppm:
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece

Up to 5000 ppm:
(APF = 1000) Any supplied-air respirator operated in a pressure-demand or other positive-pressure mode

Emergency or planned entry into unknown concentrations or IDLH conditions:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 1106
Page last reviewed: October 30, 2019