# NIOSH Pocket Guide to Chemical Hazards
Carbon monoxide | CAS 630-08-0
CO | RTECS FG3500000
Synonyms & Trade Names Carbon oxide, Flue gas, Monoxide | DOT ID & Guide 1016 119 9202 168 (cryogenic liquid)
Exposure Limits | NIOSH REL: TWA 35 ppm (40 mg/m3) C 200 ppm (229 mg/m3)
OSHA PEL†: TWA 50 ppm (55 mg/m3)
IDLH 1200 ppm | Conversion 1 ppm = 1.15 mg/m3
Physical Description Colorless, odorless gas. [Note: Shipped as a nonliquefied or liquefied compressed gas.]
MW: 28.0 | BP: -313°F | MLT: -337°F | Sol: 2%
VP: >35 atm | IP: 14.01 eV | RGasD: 0.97 |
Fl.P: NA (Gas) | UEL: 74% | LEL: 12.5% |
Flammable Gas
Incompatibilities & Reactivities Strong oxidizers, bromine trifluoride, chlorine trifluoride, lithium
Measurement Methods NIOSH 6604; OSHA ID209
Personal Protection & Sanitation Skin: Frostbite Eyes: Frostbite Wash skin: No recommendation Remove: When wet (flammable) Change: No recommendation Provide: Frostbite | 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
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
See also: INTRODUCTION