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Carbon dioxide

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Synonyms & Trade Names
Carbonic acid gas, Dry ice [Note: Normal constituent of air (about 300 ppm)].
CAS No.
124-38-9
RTECS No.
FF6400000
DOT ID & Guide
1013 120
1845 120(dry ice)
2187 120(liquid)
Formula
CO₂
Conversion
1 ppm = 1.80 mg/m3
IDLH
40,000 ppm
See: 124389
Exposure Limits
NIOSH REL
TWA 5000 ppm (9000 mg/m3) ST 30,000 ppm (54,000 mg/m3)
OSHA PEL
TWA 5000 ppm (9000 mg/m3) See Appendix G
Measurement Methods
NIOSH 6603;
OSHA ID172
See: NMAM or OSHA Methods
Physical Description
Colorless, odorless gas. [Note: Shipped as a liquefied compressed gas. Solid form is utilized as dry ice.]
Molecular Weight
44.0
Boiling Point
Sublimes
Melting Point
-109°F (Sublimes)
Solubility
(77°F): 0.2%
Vapor Pressure
56.5 atm
Ionization Potential
13.77 eV
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Relative Gas Density
1.53
Nonflammable Gas
Incompatibilities & Reactivities
Dusts of various metals, such as magnesium, zirconium, titanium, aluminum, chromium & manganese are ignitable and explosive when suspended in carbon dioxide. Forms carbonic acid in water.
Exposure Routes
inhalation, skin and/or eye contact (liquid/solid)
Symptoms
headache, dizziness, restlessness, paresthesia; dyspnea (breathing difficulty); sweating, malaise (vague feeling of discomfort); increased heart rate, cardiac output, blood pressure; coma; asphyxia; convulsions; frostbite (liquid, dry ice)
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/OSHA

Up to 40000 ppm:
(APF = 10) Any supplied-air respirator
(APF = 50) Any self-contained breathing apparatus with a full facepiece

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:
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0021
Page last reviewed: October 30, 2019
Content source: National Institute for Occupational Safety and Health