NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

Cesium hydroxide

CAS
21351-79-1

CsOH

RTECS
FK9800000
Synonyms & Trade Names

Cesium hydrate, Cesium hydroxide dimer
DOT ID & Guide
2682 / 157
2681 / 154 (solution)

Exposure
Limits

NIOSH REL: TWA 2 mg/m3
OSHA PEL: none
IDLH
N.D. See: IDLH INDEX
Conversion
Physical Description
Colorless or yellowish, crystalline solid. [Note: Hygroscopic (i.e., absorbs moisture from the air).]
MW: 149.9
BP: ?
MLT: 522°F
Sol(59°F): 395%
VP: 0 mmHg (approx)
IP: NA

Sp.Gr: 3.68
Fl.P: NA
UEL: NA
LEL: NA

Noncombustible Solid
Incompatibilities & Reactivities

Water, acids, CO2, metals (e.g., Al, Pb, Sn, Zn), oxygen [Note: CsOH is a strong base, causing the generation of considerable heat in contact with water or moisture.]
Measurement Methods
None available
See: NMAM or OSHA Methods
Personal Protection & Sanitation
(See protection)
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
Not available.
Important additional information about respirator selection
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
Irritation eyes, skin, upper respiratory system; eye, skin burns
Target Organs
Eyes, skin, respiratory system
See also: INTRODUCTION