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DIACETYL
| CAS # | 431-03-8 |
|---|---|
| Formula |
C₄H₆O₂ |
| Synonyms |
biacetyl; 2,3-butanedione, 2,3-butadione, 2,3-diketobutane, dimethyl diketone, dimethylglyoxal, glyoxal, dimethyl- |
| Physical description | Colorless liquid with a strong chlorine-like odor. | ||
|---|---|---|---|
| Boiling point | 190°F | Molecular weight | 86.09 |
| Freezing point/melting point | 27.7°F | Vapor pressure | |
| Flash point | 80°F | Vapor density | 3 |
| Specific gravity | 0.99 at 59°F | Ionization potential | |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| NFPA health rating | 2 | NFPA fire rating | 3 |
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | D740 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | 2 Specially dried silica gel tubes in series; each tube has a single 600 mg section and a GFF, filter faces forward when sampling [SKC 226-183] |
| Sampling time* | 180 min |
| Sampling volume (TWA)* | 9 L |
| Sampling flow rate (TWA)* | 0.05 L/min |
| Sampling volume (STEL/Peak/C)* | 3 L |
| Sampling flow rate (STEL/Peak/C)* | 0.2 L/min |
| Analytical method instruments | GC-FID |
| Method reference | OSHA 1012 (fully validated) |
| Notes | Use an opaque tube holder or wrap tubes with aluminum foil or other opaque material while sampling. Separate the two tubes and cap both ends of each tube as soon as possible after sampling. Individually seal the two tubes. Protect tubes from light after sampling. |
| 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 |
5 ppb (0.005 ppm) 8-hr TWA [2.6 ppb (0.0026 ppm) Action Level] |
TLV-TWA |
0.01 ppm [2011] |
PEL-TWA | ||
| PEL-STEL | REL-STEL |
25 ppb (0.025 ppm) [15 minutes] |
TLV-STEL |
0.02 ppm [2011] |
PEL-STEL | ||
| PEL-C | REL-C | TLV-C | PEL-C | ||||
| Skin notation |
NA |
Skin notation |
NA |
Skin notation |
N |
Skin notation |
NA |
|
Notes:
Not established |
Notes: | Notes: |
Notes:
Not established |
||||
| Health factors: See NIH-NLM PubChem. | IDLH | ||||||
| Carcinogenic classifications: TLV-A4 | Notes: | ||||||
| AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: | |||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Diacetyl NIOSH: Pocket Guide to Chemical Hazards - Diacetyl Literature References
|
Last Updated Date : 12/22/2020