Calcium sulfate hemihydrate

  • Plaster of Paris
  • Sulfuric acid, calcium salt, hydrate (2:2:1)
Formula
2CaSO4 . H2O
Structure
Description
white powder

Registry Numbers and Inventories.
CAS
10034-76-1
RTECS
EW4150000
Beilstein/Gmelin
77181 (G)
Austrailia AICS
Listed
New Zealand
Listed

Properties.
Formula
2CaO4S.H2O
Formula mass
290.30
Density
2.73 g/cm3

Hazards and Protection.
Storage
Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.
Handling
Use with adequate ventilation. Minimize dust generation and accumulation. Avoid contact with skin and eyes. Avoid ingestion and inhalation.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to minimize contact with skin.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Vacuum or sweep up material and place into a suitable disposal container.
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Calcium sulfate is incompatible with aluminum and diazonethane. At high temperatures, mixtures of calcium sulfate and phosphorus ignites.
Decomposition
Oxides of sulfur.

Fire.
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Extinguishing media: Substance is noncombustible; use agent most appropriate to extinguish surrounding fire.
Health
1
 
Flammability
0
 
 
Reactivity
0
 

Health.
Exposure effects
Prolonged inhalation may cause respiratory tract inflammation and lung damage.
   Ingestion
Ingestion of large amounts may cause gastrointestinal irritation. May cause mechanical obstruction of the digestive
   Inhalation
Dust is irritating to the respiratory tract.
   Skin
Causes skin irritation.
   Eyes
Causes eye irritation. May cause conjunctivitis.

First aid
 
   Ingestion
If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   Skin
Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.