PAC Database - Detailed Chemical Data
Chemical Identity
| Chemical | CAS# | UN# | Health Code Numbers | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tetramethylsilane | 75-76-3 | 2749 |
18.00
16.01
|
|||||||||
| Formula | Synonyms | |||||||||||
| C4H12Si | TETRAMETHYLSILANE, SILANE, TETRAMETHYL-, TÉTRAMÉTHYLSILANE (DOT FRENCH), TETRAMETILSILANO (DOT SPANISH), TMS, TMS (SILANE DERIVATIVE) | |||||||||||
Physical Properties
| Mol Wt | State | MP (°C) | BP (°C) | VP (Hg) | VP (°C) | SG | LEL (ppm) |
|---|---|---|---|---|---|---|---|
| 88.23 | L/S | -99 | 0.648 |
PAC Values
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 100 | 130 | 270 |
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 360 | 470 | 970 |
Technical Basis
Tetramethylsilane is a complex form of silane where the hydrogen atoms are replaced with methyl groups. A review of available sources did not identify acute toxicity data or exposure limits for tetramethylsilane. Instead, analysts evaluated exposure limits for silane (AEGLs, CASRN: 7803-62-5) and methane (CASRN: 74-82-8) for TEEL development. Of these, silane is more toxic than methane, which is primarily an asphyxiation hazard. Considering this, analysts selected the AEGLs for silane due to their priority among Protective Action Criteria (Section 1).
• PAC-1 = AEGL-1 (Silane, CASRN: 7803-62-5)
• PAC-2 = AEGL-2 (Silane, CASRN: 7803-62-5)
• PAC-3 = AEGL-3 (Silane, CASRN: 7803-62-5)
This review generated PAC values inconsistent with Rev. 29A. The Rev. 29A and current sources are consistent, AEGLs for silane (CASRN: 7803-62-5). Differences in values report are due to Rev. 29A applying a molecular weight adjustment; the current ppm values are unmodified, per Section 3.2.2.
• PAC-1 = AEGL-1 (Silane, CASRN: 7803-62-5)
• PAC-2 = AEGL-2 (Silane, CASRN: 7803-62-5)
• PAC-3 = AEGL-3 (Silane, CASRN: 7803-62-5)
This review generated PAC values inconsistent with Rev. 29A. The Rev. 29A and current sources are consistent, AEGLs for silane (CASRN: 7803-62-5). Differences in values report are due to Rev. 29A applying a molecular weight adjustment; the current ppm values are unmodified, per Section 3.2.2.
References
Chemical information: https://pubchem.ncbi.nlm.nih.gov/compound/6396
Silane AEGLs retrieved from: https://www.epa.gov/aegl/silane-results-aegl-program
Methane information: https://pubchem.ncbi.nlm.nih.gov/compound/297