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Potassium hydroxide

Synonyms & Trade Names
Caustic potash, Lye [Potassium hydroxide], Potassium hydrate
CAS No.
1310-58-3
RTECS No.
DOT ID & Guide
1813 154(dry, solid)
1814 154(solution)
Formula
KOH
Conversion
IDLH
N.D.
See: IDLH INDEX
Exposure Limits
NIOSH REL
C 2 mg/m3
OSHA PEL
none See Appendix G
Measurement Methods
NIOSH 7401
See: NMAM or OSHA Methods
Physical Description
Odorless, white or slightly yellow lumps, rods, flakes, sticks, or pellets. [Note: May be used as an aqueous solution.]
Molecular Weight
56.1
Boiling Point
2415°F
Melting Point
716°F
Solubility
(59°F): 107%
Vapor Pressure
(1317°F): 1 mmHg
Ionization Potential
?
Specific Gravity
2.04
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Noncombustible Solid; however, may react with H2O & other substances
and generate sufficient heat to ignite combustible materials.
Incompatibilities & Reactivities
Acids, water, metals (when wet), halogenated hydrocarbons, maleic anhydride [Note: Heat is generated if KOH comes in contact with H2O & CO2 from the air.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, respiratory system; cough, sneezing; eye, skin burns; vomiting, diarrhea
Target Organs
Eyes, skin, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:Daily
Provide:Eyewash, Quick drench
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Water flush immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations
See also
INTRODUCTION   ICSC CARD: 0357
Page last reviewed: October 30, 2019