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α-METHYL STYRENE†
| CAS # | 98-83-9 |
|---|---|
| Formula |
C₉H₁₀ |
| Synonyms |
benzoic trichloride |
| Physical description | Colorless liquid with a characteristic odor. | ||
|---|---|---|---|
| Boiling point | 330°F | Molecular weight | 118.2 |
| Freezing point/melting point | -10°F | Vapor pressure | 2 mmHg |
| Flash point | 129°F | Vapor density | 4.08 |
| Specific gravity | 0.91 | Ionization potential | 8.35 eV |
| Lower explosive limit (LEL) | 1.9% | Upper explosive limit (UEL) | 6.1% |
| NFPA health rating | 1 | NFPA fire rating | 2 |
| NFPA reactivity rating | 1 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1782 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | CSC tube (100/50 mg) [SKC 226-01] |
| Sampling time* | |
| Sampling volume (TWA)* | 1-30 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 1501 (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 | Detector tube | Infrared spectrophotometer | Infrared spectrophotometer |
|---|---|---|---|
| Model/Type | Matheson-Kitagawa 8014-193S | Miran 1A & 1B | Miran 103 |
|
Sampling information (see manufacturer instructions) |
follow mfr instructions, 10-500 ppm range | 0.7 ppm@11.3 µm | 0-100 ppm@11.3 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 | REL-TWA |
50 ppm |
TLV-TWA |
10 ppm [2009] |
PEL-TWA |
50 ppm (240 mg/m³) |
|
| PEL-STEL | REL-STEL |
100 ppm |
TLV-STEL | PEL-STEL |
100 ppm (485 mg/m³) |
||
| PEL-C |
100 ppm (480 mg/m³) |
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 |
700 ppm |
|||||
| Carcinogenic classifications: TLV-A3 | Notes: | ||||||
| AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: | |||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Isopropenylbenzene NIOSH: Pocket Guide to Chemical Hazards - ⍺-Methyl styrene Literature References
|
Last Updated Date : 01/14/2021