CALCIUM HYDROXIDE†
| CAS # | 1305-62-0 |
|---|---|
| Formula |
Ca(OH)₂ |
| Synonyms |
calcium hydrate; caustic lime; hydrated lime; slaked lime |
| Physical description | White, odorless powder. | ||
|---|---|---|---|
| Boiling point | decomposes | Molecular weight | 74.1 |
| Freezing point/melting point | 1076°F (decomposes) (loses H₂O) | Vapor pressure | 0 mmHg (approx) |
| Flash point | Vapor density | ||
| Specific gravity | 2.24 | Ionization potential | |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| NFPA health rating | NFPA fire rating | ||
| NFPA reactivity rating | NFPA special instruction | ||
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 0515 (total); request using analyte code 9135 | C330 (resp); request using analyte code 9130 | |
|---|---|---|---|
| Sampling group | |||
| Sampler/Sampling media | Tared low-ash 37 mm PVC filter, 5 microns [SLTC108] | Tared low-ash 37 mm PVC filter, 5 microns, preceded by 10 mm nylon Dorr-Oliver cyclone for respirable samples. [SLTC108] | |
| Sampling time* | 240-480 min |
240-480 min |
|
| Sampling volume (TWA)* | 960 L |
816 L |
|
| Sampling flow rate (TWA)* | 2 L/min |
1.7 L/min ±5% |
|
| Sampling volume (STEL/Peak/C)* | |||
| Sampling flow rate (STEL/Peak/C)* | |||
| Analytical method instruments | Gravimetric | Gravimetric | |
| Method reference | OSHA PV2121 (partially validated) | OSHA PV2121 (partially validated) | |
| Notes | Samples collected for this compound are first analyzed gravimetrically. If the gravimetric result of a sample yields a concentration below the permissible exposure limit (PEL), the SLTC will report the calculated air concentration for the requested compound solely from the gravimetric result, qualified as less than or equal to the gravimetric result; no further work on the sample will be performed. If the gravimetric result indicates an air concentration greater than the PEL, the sample will proceed for elemental analysis. Results will be reported from the elemental analysis for the element only; the stated identity of the actual sample contents is based on the assumption that the material sampled is as identified by the compliance officer using available documentation of materials and processes. An elemental result provided may be converted to the desired compound by multiplying the result by the appropriate stoichiometric factor. A 91B report specific to the compound (including the stoichiometric conversion) may by be provided upon request by contacting the laboratory. The stoichiometric factor for calcium hydroxide from calcium is 1.849. |
Samples collected for this compound are first analyzed gravimetrically. If the gravimetric result of a sample yields a concentration below the permissible exposure limit (PEL), the SLTC will report the calculated air concentration for the requested compound solely from the gravimetric result, qualified as less than or equal to the gravimetric result; no further work on the sample will be performed. If the gravimetric result indicates an air concentration greater than the PEL, the sample will proceed for elemental analysis. Results will be reported from the elemental analysis for the element only; the stated identity of the actual sample contents is based on the assumption that the material sampled is as identified by the compliance officer using available documentation of materials and processes. An elemental result provided may be converted to the desired compound by multiplying the result by the appropriate stoichiometric factor. A 91B report specific to the compound (including the stoichiometric conversion) may by be provided upon request by contacting the laboratory. The stoichiometric factor for calcium hydroxide from calcium is 1.849. The standard applies to the Respirable Fraction. |
|
| Special requirements | FOR TOTAL DUST, DO NOT USE A CYCLONE!!! |
Samples must be collected with a Dorr-Oliver cyclone. |
* 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 |
15 mg/m³ (total dust), 5 mg/m³ (respirable fraction) |
REL-TWA |
5 mg/m³ |
TLV-TWA | PEL-TWA |
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:
Visit the ACGIH TLV site for specific data |
Notes: | ||||
| Health factors: See NIH-NLM PubChem. | IDLH | ||||||
| Carcinogenic classifications: Not listed | Notes: | ||||||
| AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: | |||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Calcium hydroxide NIOSH: Pocket Guide to Chemical Hazards - Calcium hydroxide Literature References
|
Last Updated Date : 04/09/2024