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TRIBUTYL PHOSPHATE†
| CAS # | 126-73-8 |
|---|---|
| Formula |
C₁₂H₂₇O₄P |
| Synonyms |
butyl phosphate; TBP; tributyl ester of phosphoric acid; tri-n-butyl phosphate |
| Physical description | Colorless to pale-yellow, odorless liquid. | ||
|---|---|---|---|
| Boiling point | 552°F | Molecular weight | 266.36 |
| Freezing point/melting point | <-112°F | Vapor pressure | 0.004 mmHg at 77°F |
| Flash point | 295°F (open cup) | Vapor density | 9.2 |
| Specific gravity | 0.982 at 68°F | Ionization potential | |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| NFPA health rating | 3 | NFPA fire rating | 1 |
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 2477 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | Mixed cellulose ester filter (MCEF) 0.8 micron (37 mm) and filter spacer with Na₂CO₃ impregnated backup pad, in a 3-piece cassette [SKC 225-9001] |
| Sampling time* | |
| Sampling volume (TWA)* | 2-100 L |
| Sampling flow rate (TWA)* | 1-3 L/min |
| Sampling volume (STEL/Peak/C)* | |
| Sampling flow rate (STEL/Peak/C)* | |
| Analytical method instruments | GC-FPD |
| Method reference | NIOSH 5034 (partially validated) |
| Notes | separate front and backup cassettes if two were used; seal cassettes firmly with plugs |
| 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 |
5 mg/m³ |
REL-TWA |
2 ppm (2.5 mg/m³) |
TLV-TWA |
5 mg/m³ (inhalable fraction and vapor) [2012] |
PEL-TWA |
0.2 ppm (2.5 mg/m³) |
| PEL-STEL | REL-STEL | TLV-STEL | PEL-STEL | ||||
| PEL-C | REL-C | TLV-C | PEL-C | ||||
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
| Notes: | Notes: |
Notes:
BEI® |
Notes: | ||||
| Health factors: See NIH-NLM PubChem. | IDLH |
30 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 - Tributyl phosphate NIOSH: Pocket Guide to Chemical Hazards - Tributyl phosphate Literature References
|
Last Updated Date : 01/28/2021