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PROPYLENE OXIDE (1,2-EPOXYPROPANE)†
| CAS # | 75-56-9 |
|---|---|
| Formula |
C₃H₆O |
| Synonyms |
1,2-epoxy propane; methyl ethylene oxide; methyloxirane; propene oxide; 1,2-propylene oxide |
| Physical description | Colorless liquid with a benzene-like odor. | ||
|---|---|---|---|
| Boiling point | 93.61°F | Molecular weight | 58.08 |
| Freezing point/melting point | -170°F | Vapor pressure | 445 mmHg |
| Flash point | -35°F | Vapor density | 2 |
| Specific gravity | 0.859 at 32°F | Ionization potential | 9.81 eV |
| Lower explosive limit (LEL) | 2.8% | Upper explosive limit (UEL) | 37% |
| NFPA health rating | 3 | NFPA fire rating | 4 |
| NFPA reactivity rating | 2 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 2215 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | Anasorb 747 (140/70 mg) [SKC 226-81A] |
| Sampling time* |
|
| Sampling volume (TWA)* |
5 L |
| Sampling flow rate (TWA)* |
0.1 L/min |
| Sampling volume (STEL/Peak/C)* |
|
| Sampling flow rate (STEL/Peak/C)* |
|
| Analytical method instruments | GC-FID |
| Method reference | OSHA 88 (fully 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 | Detector tube | Detector tube |
|---|---|---|
| Model/Type | Gastec 163 | Matheson-Kitagawa 8014-163SA |
|
Sampling information (see manufacturer instructions) |
1 stroke, approx 0.03-3.9% range, uncertainty 25% for 0.06-1.3%, 16% for 1.3-3.9% | 0.5 or 1 stroke, approx 0.05-5% range |
|
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 |
100 ppm (240 mg/m³) |
REL-TWA |
|
TLV-TWA |
2 ppm [2000] |
PEL-TWA |
2 ppm (4.75 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
|
PEL-STEL |
|
| PEL-C |
|
REL-C |
|
TLV-C |
|
PEL-C |
|
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
| Notes: |
Notes:
CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION (LOQ 8.4 ppm). See Appendix A, NIOSH Potential Occupational Carcinogens. |
Notes:
dermal sensitization (DSEN) |
Notes:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
400 ppm |
|||||
| Carcinogenic classifications: IARC-2B, NIOSH-Ca, NTP-R, TLV-A3, EPA-B2 |
Notes:
Ca |
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
50 ppm/250 ppm/750 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Propylene oxide NIOSH: Pocket Guide to Chemical Hazards - Propylene oxide Literature References
|
Last Updated Date : 01/11/2021