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MESITYL OXIDE†
| CAS # | 141-79-7 |
|---|---|
| Formula |
C₆H₁₀O |
| Synonyms |
isobutenyl methyl ketone; isopropylideneacetone; methyl isobutenyl ketone; 4-methyl-3-penten-2-one |
| Physical description | Oily, colorless to light-yellow liquid with a peppermint- or honey-like odor. | ||
|---|---|---|---|
| Boiling point | 266°F | Molecular weight | 98.2 |
| Freezing point/melting point | -52°F | Vapor pressure | 9 mmHg |
| Flash point | 87°F | Vapor density | |
| Specific gravity | 0.853 at 68°F | Ionization potential | 9.08 eV |
| Lower explosive limit (LEL) | 1.4% | Upper explosive limit (UEL) | 7.2% |
| NFPA health rating | 3 | NFPA fire rating | 3 |
| NFPA reactivity rating | 1 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1635 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | CSC tube (100/50 mg) [SKC 226-01] |
| Sampling time* | |
| Sampling volume (TWA)* | 1-25 L |
| Sampling flow rate (TWA)* | 0.01-0.2 L/min |
| Sampling volume (STEL/Peak/C)* |
|
| Sampling flow rate (STEL/Peak/C)* |
|
| Analytical method instruments | GC-FID |
| Method reference | NIOSH 1301 (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 | Infrared spectrophotometer |
|---|---|---|
| Model/Type | Matheson-Kitagawa 8014-190U | Miran 1A & 1B |
|
Sampling information (see manufacturer instructions) |
5-100 ppm range | 0.8 ppm@8.2 µm |
|
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 |
25 ppm (100 mg/m³) |
REL-TWA |
10 ppm (40 mg/m³) |
TLV-TWA |
15 ppm [1992] |
PEL-TWA |
15 ppm (60 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
25 ppm [1992] |
PEL-STEL |
25 ppm (100 mg/m³) |
| PEL-C |
|
REL-C |
|
TLV-C |
|
PEL-C |
|
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
| Notes: |
Notes:
|
Notes:
|
Notes:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
1400 ppm |
|||||
| Carcinogenic classifications: Not listed |
Notes:
10 % of LEL |
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
|
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Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Mesityl oxide NIOSH: Pocket Guide to Chemical Hazards - Mesityl oxide Literature References
|
Last Updated Date : 01/04/2021