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METHYL SILICATE†
| CAS # | 681-84-5 |
|---|---|
| Formula |
C₄H₁₂O₄Si |
| Synonyms |
methyl orthosilicate; tetramethoxysilane; tetramethyl ester of silicic acid; tetramethyl silicate |
| Physical description | Clear, colorless liquid. | ||
|---|---|---|---|
| Boiling point | 250°F | Molecular weight | 152.3 |
| Freezing point/melting point | 28°F | Vapor pressure | 12 mmHg at 77°F |
| Flash point | 205°F | Vapor density | |
| Specific gravity | 1.02 | Ionization potential | |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| 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.) | |||
|---|---|---|---|
| Sampling group | |||
| Sampler/Sampling media | |||
| Sampling time* | |||
| Sampling volume (TWA)* | |||
| Sampling flow rate (TWA)* | |||
| Sampling volume (STEL/Peak/C)* | |||
| Sampling flow rate (STEL/Peak/C)* | |||
| Analytical method instruments | |||
| Method reference | |||
| 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 | |||||
|---|---|---|---|---|---|
| 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 |
1 ppm (6 mg/m³) |
TLV-TWA |
1 ppm [1978] |
PEL-TWA |
1 ppm (6 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
|
PEL-STEL |
|
| PEL-C |
5 ppm (30 mg/m³) |
REL-C |
|
TLV-C |
|
PEL-C |
|
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
|
Notes:
The OSHA PEL applies to Construction and Maritime Industries only. See 29 CFR 1926.55 Table 1 and 29 CFR 1915.1000 Table Z-Shipyards. |
Notes:
|
Notes:
|
Notes:
|
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| Health factors: See NIH-NLM PubChem. | IDLH | ||||||
| Carcinogenic classifications: Not listed |
Notes:
|
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
--/10 ppm/20 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Methyl orthosilicate NIOSH: Pocket Guide to Chemical Hazards - Methyl silicate Literature References
|
Last Updated Date : 06/01/2022