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CYCLOPENTANE
| CAS # | 287-92-3 | 
|---|---|
| Formula | C₅H₁₀ | 
| Synonyms | pentamethylene | 
| Physical description | Colorless liquid with a mild, sweet odor. | ||
|---|---|---|---|
| Boiling point | 121°F | Molecular weight | 70.2 | 
| Freezing point/melting point | -137°F | Vapor pressure | 400 mmHg at 88°F | 
| Flash point | <20°F | Vapor density | |
| Specific gravity | 0.75 | Ionization potential | 10.52 eV | 
| Lower explosive limit (LEL) | 1.1% | Upper explosive limit (UEL) | 8.7% | 
| NFPA health rating | 1 | NFPA fire rating | 3 | 
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | C619 | 
|---|---|
| Sampling group | |
| Sampler/Sampling media | CSC tube (100/50 mg) [SKC 226-01] | 
| Sampling time* | |
| Sampling volume (TWA)* | 4 L | 
| Sampling flow rate (TWA)* | 0.2 L/min | 
| Sampling volume (STEL/Peak/C)* | |
| Sampling flow rate (STEL/Peak/C)* | |
| Analytical method instruments | GC-FID | 
| Method reference | NIOSH 1500 (partially validated) | 
| Notes | |
| Special requirements | 
* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.
| Wipe Sampler/Sampling media | |
|---|---|
| Bulk Method | 
| Device | |||||
|---|---|---|---|---|---|
| Model/Type | |||||
| Sampling information (see manufacturer instructions) | 
| 
                                  OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak | 
                                  NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling | 
                                  ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling | |||||
|---|---|---|---|---|---|---|---|
| PEL-TWA | REL-TWA | 600 ppm (1720 mg/m³) | TLV-TWA | 1000 ppm [2021] | PEL-TWA | 600 ppm (1720 mg/m³) | |
| PEL-STEL | REL-STEL | TLV-STEL | PEL-STEL | ||||
| PEL-C | REL-C | TLV-C | PEL-C | ||||
| Skin notation | NA | Skin notation | N | Skin notation | N | Skin notation | N | 
| Notes: Not established | Notes: | Notes: (EX) Explosion hazard: the substance is a flammable asphyxiant or excursions above the TLV could approach 10% of the LEL. | Notes: | ||||
| Health factors: See NIH-NLM PubChem. | IDLH | ||||||
| Carcinogenic classifications: Not listed | Notes: | ||||||
| AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: | |||||||
Additional Resources and Literature References
| NOAA: CAMEO Chemicals - Cyclopentane NIOSH: Pocket Guide to Chemical Hazards - Cyclopentane Literature References 
 | 
Last Updated Date : 12/22/2020
