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Cyclopentadiene

Synonyms & Trade Names
1,3-Cyclopentadiene
CAS No.
542-92-7
RTECS No.
DOT ID & Guide
Formula
C₅H₆
Conversion
1 ppm = 2.70 mg/m3
IDLH
750 ppm
See: 542927
Exposure Limits
NIOSH REL
TWA 75 ppm (200 mg/m3)
OSHA PEL
TWA 75 ppm (200 mg/m3)
Measurement Methods
NIOSH 2523
See: NMAM or OSHA Methods
Physical Description
Colorless liquid with an irritating, terpene-like odor.
Molecular Weight
66.1
Boiling Point
107°F
Freezing Point
-121°F
Solubility
Insoluble
Vapor Pressure
400 mmHg
Ionization Potential
8.56 eV
Specific Gravity
0.80
Flash Point
(oc) 77°F
Upper Explosive Limit
?
Lower Explosive Limit
?
Class IC Flammable Liquid: Fl.P. at or above 73°F and below 100°F.
Incompatibilities & Reactivities
Strong oxidizers, fuming nitric acid, sulfuric acid [Note: Polymerizes to dicyclopentadiene upon standing.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, nose
Target Organs
Eyes, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet (flammable)
Change:No recommendation
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash promptly
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH/OSHA

Up to 750 ppm:
(APF = 10) Any chemical cartridge respirator with organic vapor cartridge(s)
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
(APF = 25) Any powered, air-purifying respirator with organic vapor cartridge(s)
(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: 0857
Page last reviewed: October 30, 2019