Label abbreviations descriptions

POTASSIUM HYDROXIDE

Chemical Identification
CAS # 1310-58-3
Formula
 

HKO
Synonyms
 

caustic potash; lye; potassium hydrate

Physical Properties
Physical description White, odorless solid or clear aqueous solution.
Boiling point 2408°F Molecular weight 56.11
Freezing point/melting point 680°F Vapor pressure 1 mmHg at 1326°F; 5 mmHg at 1497°F
Flash point Vapor density
Specific gravity 2.04 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.) 2140
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)*
 

 
Sampling flow rate (STEL/Peak/C)*
 

 
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 potassium hydroxide from potassium is 1.435.

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
 

 

 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
 

NA

 Skin notation
 

N

 Skin notation
 

N

 Skin notation
 

N
Notes:
 

Not established

 Notes:
 

 

 Notes:
 

 

 Notes:
 

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

 
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
 

 

Additional Resources and Literature References

Last Updated Date : 01/08/2021