SODIUM HYDROXIDE†

Chemical Identification

CAS # 1310-73-2
Formula

NaOH

Synonyms

caustic soda; lye; soda lye; sodium hydrate

Physical Properties

Physical description Colorless to white, odorless solid (flakes, beads, granular form).
Boiling point 2534°F Molecular weight 40
Freezing point/melting point 605°F Vapor pressure 0 mmHg (approx)
Flash point Vapor density
Specific gravity 2.13 Ionization potential
Lower explosive limit (LEL) Upper explosive limit (UEL)
NFPA health rating 3 NFPA fire rating 0
NFPA reactivity rating 1 NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA

Analyte code (IMIS no.) 2260
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*

240-480 min

Sampling volume (TWA)*

480-960 L

Sampling flow rate (TWA)*

2 L/min

Sampling volume (STEL/Peak/C)*

30 L(15 min - C)

Sampling flow rate (STEL/Peak/C)*

2 L/min

Analytical method instruments AAS/AES
Method reference OSHA ID-121 (fully validated)
Notes

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 sodium hydroxide from sodium is 1.740.

Analysis for this analyte is based on water solubility.

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.

Bulk/Wipe Method

Wipe Sampler/Sampling media
Bulk Method

This analysis is for the metal component of this analyte only. The conversion back to the analyte is a mathematical one assuming all metal present is from the analyte source.

On-Site Screening Techniques

Device
Model/Type
Sampling information
(see manufacturer instructions)

Exposure Limits

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
CAL/OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
PEL-TWA

2 mg/m³

REL-TWA TLV-TWA PEL-TWA
PEL-STEL REL-STEL TLV-STEL PEL-STEL
PEL-C REL-C

2 mg/m³

TLV-C

2 mg/m³ [1992]

PEL-C

2 mg/m³

Skin notation

N

Skin notation

N

Skin notation

N

Skin notation

N

Notes:

See 29 CFR 1910.1000 Table Z-1.

Notes: Notes: Notes:
Health factors:  See NIH-NLM PubChem. IDLH

10 mg/m³

Carcinogenic classifications: Not listed Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

0.5 mg/m³/5 mg/m³/50 mg/m³

Additional Resources and Literature References

Last Updated Date : 01/12/2021