NIOSH logo and tagline

Ketene

Synonyms & Trade Names
Carbomethene, Ethenone, Keto-ethylene
CAS No.
463-51-4
RTECS No.
DOT ID & Guide
Formula
CH₂=CO
Conversion
1 ppm = 1.72 mg/m3
IDLH
5 ppm
See: 463514
Exposure Limits
NIOSH REL
TWA 0.5 ppm (0.9 mg/m3) ST 1.5 ppm (3 mg/m3)
OSHA PEL
TWA 0.5 ppm (0.9 mg/m3) See Appendix G
Measurement Methods
NIOSH S92 (II-2)
See: NMAM or OSHA Methods
Physical Description
Colorless gas with a penetrating odor.
Molecular Weight
42.0
Boiling Point
-69°F
Freezing Point
-238°F
Solubility
Reacts
Vapor Pressure
>1 atm
Ionization Potential
9.61 eV
Flash Point
NA (Gas)
Upper Explosive Limit
?
Lower Explosive Limit
?
Relative Gas Density
1.45
Flammable Gas
Incompatibilities & Reactivities
Water, alcohols, ammonia [Note: Readily polymerizes. Reacts with water to form acetic acid.]
Exposure Routes
inhalation, skin and/or eye contact
Symptoms
irritation eyes, skin, nose, throat, respiratory system; pulmonary edema
Target Organs
Eyes, skin, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin:No recommendation
Eyes:No recommendation
Wash skin:No recommendation
Remove:No recommendation
Change:No recommendation
First Aid
(See procedures)


Breathing:Respiratory support
Respirator Recommendations

NIOSH/OSHA

Up to 5 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:
(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: 0812   MEDICAL TESTS: 0126
Page last reviewed: October 30, 2019