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Carbon monoxide

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Synonyms & Trade Names
Carbon oxide, Flue gas, Monoxide
CAS No.
630-08-0
RTECS No.
FG3500000
DOT ID & Guide
1016 119
9202 168(cryogenic liquid)
Formula
CO
Conversion
1 ppm = 1.15 mg/m3
IDLH
1200 ppm
See: 630080
Exposure Limits
NIOSH REL
TWA 35 ppm (40 mg/m3) C 200 ppm (229 mg/m3)
OSHA PEL
TWA 50 ppm (55 mg/m3) See Appendix G
Measurement Methods
NIOSH 6604;
OSHA ID209 , ID210
See: NMAM or OSHA Methods
Physical Description
Colorless, odorless gas. [Note: Shipped as a nonliquefied or liquefied compressed gas.]
Molecular Weight
28.0
Boiling Point
-313°F
Melting Point
-337°F
Solubility
2%
Vapor Pressure
>35 atm
Ionization Potential
14.01 eV
Flash Point
NA (Gas)
Upper Explosive Limit
74%
Lower Explosive Limit
12.5%
Relative Gas Density
0.97
Flammable Gas
Incompatibilities & Reactivities
Strong oxidizers, bromine trifluoride, chlorine trifluoride, lithium
Exposure Routes
inhalation, skin and/or eye contact (liquid)
Symptoms
headache, tachypnea, nausea, lassitude (weakness, exhaustion), dizziness, confusion, hallucinations; cyanosis; depressed S-T segment of electrocardiogram, angina, syncope
Target Organs
cardiovascular system, lungs, blood, central nervous system
Personal Protection/Sanitation
(See protection codes)
Skin:Frostbite
Eyes:Frostbite
Wash skin:No recommendation
Remove:When wet (flammable)
Change:No recommendation
Provide:Frostbite wash
First Aid
(See procedures)
Eye:Frostbite
Skin:Frostbite
Breathing:Respiratory support
Respirator Recommendations

NIOSH

Up to 350 ppm:
(APF = 10) Any supplied-air respirator

Up to 875 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode

Up to 1200 ppm:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concern†
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator 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:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concern†
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0023   MEDICAL TESTS: 0040
Page last reviewed: October 30, 2019
Content source: National Institute for Occupational Safety and Health