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PHOSPHORIC ACID†
| CAS # | 7664-38-2 |
|---|---|
| Formula |
H₃PO₄ |
| Synonyms |
white phosphoric acid; orthophosphoric acid; metaphosphoric acid |
| Physical description | Thick, colorless, odorless, crystalline solid. | ||
|---|---|---|---|
| Boiling point | 415°F | Molecular weight | 98 |
| Freezing point/melting point | 108°F | Vapor pressure | 0.03 mmHg |
| Flash point | Vapor density | ||
| Specific gravity | 1.87 (pure) 1.33 (50% solution) | Ionization potential | |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| NFPA health rating | 3 | NFPA fire rating | 0 |
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 2085 |
|---|---|
| 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* |
480 min |
| Sampling volume (TWA)* |
960 L |
| Sampling flow rate (TWA)* |
2 L/min |
| Sampling volume (STEL/Peak/C)* |
30 L |
| Sampling flow rate (STEL/Peak/C)* |
2 L/min |
| Analytical method instruments | IC |
| Method reference | OSHA ID-111 (partially validated) |
| Notes |
If the filter is not overloaded, samples may be collected up to an 8-hour period. Within 1 hour after sampling, transfer the filter to a clean screw cap vial. Phosphoric and sulfuric acid may be submitted on the same filter; otherwise, submit as a separate filter. Large quantities of any one of the analytes can result in masking of the peaks of other analytes. |
| 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 |
Wipe with mixed cellulose ester filter (MCEF) 0.8 micron (37 mm). [AAWP03700] |
|---|---|
| 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 |
1 mg/m³ |
REL-TWA |
1 mg/m³ |
TLV-TWA |
1 mg/m³ [1992] |
PEL-TWA |
1 mg/m³ |
| PEL-STEL |
|
REL-STEL |
3 mg/m³ |
TLV-STEL |
3 mg/m³ [1992] |
PEL-STEL |
3 mg/m³ |
| PEL-C |
|
REL-C |
|
TLV-C |
|
PEL-C |
|
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
| Notes: |
Notes:
|
Notes:
|
Notes:
|
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| Health factors: See NIH-NLM PubChem. | IDLH |
1000 mg/m³ |
|||||
| Carcinogenic classifications: Not listed |
Notes:
|
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
3 mg/m³/30 mg/m³/150 mg/m³ |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Phosphoric acid NIOSH: Pocket Guide to Chemical Hazards - Phosphoric acid Literature References
|
Last Updated Date : 01/08/2021