Plaster of Paris
- Calcium sulfate hemihydrate
- Gypsum hemihydrate
2CaSO4 . H2O
Fine, odorless, tasteless powder.
Registry Numbers and Inventories.
2CaO4S . H2O
Melting point, °C
2.7 g/cm3 (20 C)
Solubility in water
Hazards and Protection.
Store in a cool, dry location. Keep containers tightly closed.
Product should be handled so as to reduce airborn dust generation.
Chemical splash goggles in compliance with OSHA regulations are advised; however, OSHA regulations also permit other type safety glasses. Whre chemical resistant gloves. To prevent repeated or prolonged skin contact, wear impervious clothing and boots.
NIOSH approved dusk mask.
Sweep up material and place in a container for disposal. Keep dust generation at a minimum. Wear protective equipment.
Stable at normal temperatures and pressures.
Strong oxidizing agents.
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use agent most appropriate to extinguish fire.
NIOSH REL: TWA 10 mg/m3 (total) TWA 5 mg/m3 (resp) OSHA PEL: TWA 15 mg/m3 (total) TWA 5 mg/m3 (resp)
Chronic bronchitis and respiratory tract leasions may result with high exposure levels.
Irritation. High concentrations may cause impaired lung function.
Seek medical attention. If individual is drowsy or unconscious, do not give anything by mouth; place individual on the left side with the head down. Contact a physician, medical facility, or poison control center for advice about whether to induce vomiting. If possible, do not leave individual unattended.
If symptoms develop, move individual away from exposure and into fresh air. If symptoms persist, seek medical attention. If breathing is difficult, administer oxygen. Keep person warm and quiet; seek immediate medical attention.
Remove contaminated clothing. Wash exposed area with soap and water. If symptoms persist, seek medical attention. Launder clothing before reuse.
If symptoms develop, immediately move individual away from exposure and into fresh air. Flush eyes gently with water for at least 15 minutes while holding eyelids apart; seek immediate medical attention.