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Acetylene

Synonyms & Trade Names
Ethine, Ethyne [Note: A compressed gas used in the welding & cutting of metals.]
CAS No.
74-86-2
RTECS No.
DOT ID & Guide
1001 116
Formula
HC≡CH
Conversion
1 ppm = 1.06 mg/m3
IDLH
N.D.
See: IDLH INDEX
Exposure Limits
NIOSH REL
C 2500 ppm (2662 mg/m3)
OSHA PEL
none
Measurement Methods
Physical Description
Colorless gas with a faint, ethereal odor. [Note: Commercial grade has a garlic-like odor. Shipped under pressure dissolved in acetone.]
Molecular Weight
26.0
Boiling Point
Sublimes
Freezing Point
-119°F (Sublimes)
Solubility
2%
Vapor Pressure
44.2 atm
Ionization Potential
11.40 eV
Flash Point
NA (Gas)
Upper Explosive Limit
100%
Lower Explosive Limit
2.5%
Relative Gas Density
0.91
Flammable Gas
Incompatibilities & Reactivities
Zinc; oxygen & other oxidizing agents such as halogens [Note: Forms explosive acetylide compounds with copper, mercury, silver & brasses (containing more than 66% copper).]
Exposure Routes
inhalation, skin and/or eye contact (liquid)
Symptoms
headache, dizziness; asphyxia; liquid: frostbite
Target Organs
central nervous system, respiratory 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:Fresh air
Respirator Recommendations
See also
INTRODUCTION   ICSC CARD: 0089
Page last reviewed: October 30, 2019