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Chemical Datasheet

CYCLOPENTANE

3 - Flammable liquid

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 287-92-3   (CYCLOPENTANE)
  • 1146
  • Flammable Liquid
  • CYP
NIOSH Pocket Guide International Chem Safety Card
Cyclopentane
  • CYCLOPENTANE
NFPA 704
Diamond Hazard Value Description
3
1 0
Blue Health 1 Can cause significant irritation.
Red Flammability 3 Can be ignited under almost all ambient temperature conditions.
Yellow Instability 0 Normally stable, even under fire conditions.
White Special
(NFPA, 2010)
General Description
A clear colorless liquid with a petroleum-like odor. Flash point of -35°F. Less dense than water and insoluble in water. Vapors are heavier than air.

Hazards

Reactivity Alerts
Air & Water Reactions
Highly flammable. Insoluble in water.
Fire Hazard
Behavior in Fire: Containers may explode. (USCG, 1999)
Health Hazard
Inhalation causes dizziness, nausea, and vomiting; concentrated vapor may cause unconsciousness and collapse. Vapor causes slight smarting of eyes. Contact with liquid causes irritation of eyes and may irritate skin if allowed to remain. Ingestion causes irritation of stomach. Aspiration produces severe lung irritation and rapidly developing pulmonary edema; central nervous system excitement followed by depression. (USCG, 1999)
Reactivity Profile
CYCLOPENTANE is incompatible with strong oxidizing agents such as chlorine, bromine, fluorine. (NIOSH, 2022).
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
Excerpt from 128 Polymerizable warning [Flammable Liquids (Water-Immiscible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 300 meters (1000 feet).

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)
Firefighting
Excerpt from 128 Polymerizable warning [Flammable Liquids (Water-Immiscible)]:

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient. CAUTION: For mixtures containing alcohol or polar solvent, alcohol-resistant foam may be more effective.

SMALL FIRE: Dry chemical, CO2, water spray or regular foam.

LARGE FIRE: Water spray, fog or regular foam. Avoid aiming straight or solid streams directly onto the product. If it can be done safely, move undamaged containers away from the area around the fire.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. For petroleum crude oil, do not spray water directly into a breached tank car. This can lead to a dangerous boil over. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2020)
Non-Fire Response
Excerpt from 128 Polymerizable warning [Flammable Liquids (Water-Immiscible)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean, non-sparking tools to collect absorbed material.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2020)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Cyclopentane:

Skin: PREVENT SKIN CONTACT - Wear appropriate personal protective clothing to prevent skin contact.

Eyes: PREVENT EYE CONTACT - Wear appropriate eye protection to prevent eye contact.

Wash skin: DAILY - The worker should wash daily at the end of each work shift, and prior to eating, drinking, smoking, etc.

Remove: WHEN WET (FLAMMABLE) - Work clothing that becomes wet should be immediately removed due to its flammability hazard (i.e., for liquids with a flash point <100°F).

Change: No recommendation is made specifying the need for the worker to change clothing after the workshift. (NIOSH, 2023)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Excerpt from NIOSH Pocket Guide for Cyclopentane:

Eye: IRRIGATE IMMEDIATELY - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: SOAP WASH - If this chemical contacts the skin, wash the contaminated skin with soap and water.

Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible.

Swallow: MEDICAL ATTENTION IMMEDIATELY - If this chemical has been swallowed, get medical attention immediately. (NIOSH, 2023)

Physical Properties

Chemical Formula:
  • C5H10
Flash Point: less than 20°F (USCG, 1999)
Lower Explosive Limit (LEL): 1.1 % (approx.) (USCG, 1999)
Upper Explosive Limit (UEL): 8.7 % (approx.) (USCG, 1999)
Autoignition Temperature: 682°F (USCG, 1999)
Melting Point: -137°F (USCG, 1999)
Vapor Pressure: 400 mmHg at 88°F (NIOSH, 2023)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 0.74 at 68°F (USCG, 1999) - Less dense than water; will float
Boiling Point: 120.7°F at 760 mmHg (USCG, 1999)
Molecular Weight: 70.1 (USCG, 1999)
Water Solubility: Insoluble (NIOSH, 2023)
Ionization Energy/Potential: 10.52 eV (NIOSH, 2023)
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Cyclopentane (287-92-3) 1800 ppm 1-flame icon indicates value is 10-49% of LEL. 3800 ppm 1-flame icon indicates value is 10-49% of LEL. 23000 ppm 3-flame icon indicates value is 100% or more of LEL. LEL = 15000 ppm
1-flame icon indicates value is 10-49% of LEL.
3-flame icon indicates value is 100% or more of LEL.
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

No regulatory information available.

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names