Lapse in Appropriations
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FORMIC ACID†
| CAS # | 64-18-6 |
|---|---|
| Formula |
CH₂O₂ |
| Synonyms |
hydrogen carboxylic acid; methanoic acid |
| Physical description | Colorless liquid with a pungent, penetrating odor. | ||
|---|---|---|---|
| Boiling point | 224°F (90% solution) | Molecular weight | 46.02 |
| Freezing point/melting point | 20°F (90% solution) | Vapor pressure | 35 mmHg |
| Flash point | 122°F (90% solution, open-cup) | Vapor density | 1.6 |
| Specific gravity | 1.22 (90% solution) | Ionization potential | 11.05 eV |
| Lower explosive limit (LEL) | 18% (90% solution) | Upper explosive limit (UEL) | 57% (90% solution) |
| NFPA health rating | 3 | NFPA fire rating | 2 |
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1310 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | Sorbent tube, silica gel, specially cleaned, 7 x 110-mm size, 2 (200/400 mg sorbent) with GS ends and WWGW separators [SKC 226-10-03] |
| Sampling time* |
|
| Sampling volume (TWA)* |
1-24 L |
| Sampling flow rate (TWA)* |
0.05 - 0.2 L/min |
| Sampling volume (STEL/Peak/C)* |
|
| Sampling flow rate (STEL/Peak/C)* |
|
| Analytical method instruments | IC |
| Method reference | NIOSH 2011 (partially validated) |
| Notes |
Samples requesting formic acid must be shipped to the laboratory ASAP and kept cold. |
| 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 ppm (9 mg/m³) |
REL-TWA |
5 ppm (9 mg/m³) |
TLV-TWA |
5 ppm [1965] |
PEL-TWA |
5 ppm (9 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
10 ppm [1965] |
PEL-STEL |
10 ppm (19 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:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
30 ppm |
|||||
| Carcinogenic classifications: Not listed |
Notes:
|
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
3 ppm/25 ppm/250 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Formic acid NIOSH: Pocket Guide to Chemical Hazards - Formic acid Literature References
|
Last Updated Date : 12/29/2020