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ACETIC ANHYDRIDE†
| CAS # | 108-24-7 |
|---|---|
| Formula |
C₄H₆O₃ |
| Synonyms |
acetic acid anhydride; acetic oxide; acetyl oxide; ethanoic anhydride |
| Physical description | Colorless liquid with a strong, pungent, vinegar-like odor. | ||
|---|---|---|---|
| Boiling point | 282°F | Molecular weight | 102.1 |
| Freezing point/melting point | -99°F | Vapor pressure | 4 mmHg |
| Flash point | 120°F | Vapor density | 3.52 |
| Specific gravity | 1.08 | Ionization potential | 10.00 eV |
| Lower explosive limit (LEL) | 2.7% | Upper explosive limit (UEL) | 10.3% |
| NFPA health rating | 3 | NFPA fire rating | 2 |
| NFPA reactivity rating | 1 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 0030 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | GFFs coated with veratrylamine (3,4-dimethoxybenzylamine) and di-n-octyl phthalate [SLTC100] |
| Sampling time* | |
| Sampling volume (TWA)* | 7.5 L |
| Sampling flow rate (TWA)* | 0.05 L/min |
| Sampling volume (STEL/Peak/C)* | |
| Sampling flow rate (STEL/Peak/C)* | |
| Analytical method instruments | GC-NPD |
| Method reference | OSHA 102 (fully validated) |
| Notes | These media are prepared by SLTC as needed and are not available for immediate shipment. Please allow time for SLTC to prepare these media prior to sampling.
|
| Special requirements | Store filters under refrigeration and use within 1 month. Small interfering peaks start appearing after that time. |
* 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 |
|---|---|
| Model/Type | Gastec 81 |
|
Sampling information (see manufacturer instructions) |
1 stroke, approx 0.3-15 ppm range, 16.4% uncertainty |
|
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 |
5 ppm (20 mg/m³) |
REL-TWA | TLV-TWA | PEL-TWA | |||
| PEL-STEL | REL-STEL | TLV-STEL | PEL-STEL | ||||
| PEL-C | REL-C |
5 ppm (20 mg/m³) |
TLV-C | PEL-C |
5 ppm (20 mg/m³) |
||
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
| Notes: | Notes: |
Notes:
Visit the ACGIH TLV site for specific data |
Notes: | ||||
| Health factors: See NIH-NLM PubChem. | IDLH |
200 ppm |
|||||
| Carcinogenic classifications: TLV-A4 | Notes: | ||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
0.5 ppm/15 ppm/100 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Acetic anhydride NIOSH: Pocket Guide to Chemical Hazards - Acetic anhydride Literature References
|
Last Updated Date : 03/27/2024