Table of contents
- Key Data
- Exposure Routes
- Fire Hazard
- Health and Safety Practice
- Regulatory Requirements
Formula: CaSiO3 or Ca2SiO4
Other names: Calcium silicate, calcium orthosilicate, CalSil
Appearance: White powder
Solubility in water: 0.095g/l. Aqueous solution has a pH of 9.9
Melting Point: 1410 - 1540°C
Respirable crystalline silica: <1% (by weight)
Wollastonite is strictly CaSiO3, but one of a range of calcium silicate compounds. Data given here is for CaSiO3, unless stated otherwise.
A fibrous silicate, but it has no bio-persistence unlike asbestos, so is not associated with the same health risks.
Small amounts of iron, magnesium or manganese may replace some of the calcium.
Used to introduce calcium with a lower LOI than whiting, so a lower risk of pinholing. It also has a lower melting point.
May cause redness of the eyes
May cause coughing
May cause indigestion
Whilst limited evidence shows that it is probably not carcinogenic, there is insufficient evidence to be certain of this.
Standard dust precutions
|_Regulator_||_8hr TWA mg/m³_||_15min TWA mg/m³_||_Notes_|
|UK HSE||10||All calcium silicates. Inhalable.|
|UK HSE||4||All calcium silicates. Respirable.|