NIOSH Pocket Guide to Chemical Hazards


CAS 13397-24-5

CaSO4 • 2H2O

RTECS MG2360000
Synonyms & Trade Names
Calcium(II) sulfate dihydrate, Gypsum stone, Hydrated calcium sulfate, Mineral white [Note: Gypsum is the dihydrate form of calcium sulfate; Plaster of Paris is the hemihydrate form.]
DOT ID & Guide


NIOSH REL: TWA 10 mg/m3 (total) TWA 5 mg/m3 (resp)
OSHA PEL: TWA 15 mg/m3 (total) TWA 5 mg/m3 (resp)
IDLH N.D. See: IDLH INDEX Conversion
Physical Description
White or nearly white, odorless, crystalline solid.
MW: 172.2
BP: ?
MLT: 262-325°F (Loses H2O)
Sol(77°F): 0.2%
VP: 0 mmHg (approx)

Sp.Gr: 2.32
Fl.P: NA

Noncombustible Solid
Incompatibilities & Reactivities
Aluminum (at high temperatures), diazomethane
Measurement Methods
NIOSH 0500, 0600
See: NMAM or OSHA Methods
Personal Protection & Sanitation (See protection)
Skin: No recommendation
Eyes: No recommendation
Wash skin: No recommendation
Remove: No recommendation
Change: No recommendation

First Aid (See procedures)
Eye: Irrigate immediately

Breathing: Fresh air

Important additional information about respirator selection
Respirator Recommendations Not available.
Exposure Routes inhalation, skin and/or eye contact
Symptoms Irritation eyes, skin, mucous membrane, upper respiratory system; cough, sneezing, rhinorrhea (discharge of thin mucus)
Target Organs Eyes, skin, respiratory system
See also: INTRODUCTION   See ICSC CARD: 1215