Calcium silicate bonded with sodium silicate. Although it is popularly considered an asbestos substitute, early uses of calcium silicate for insulation still made use of asbestos fibers. It is used in passive fire protection and fireproofing as calcium silicate brick or in roof tiles. It is one of the most successful materials in fireproofing in Europe because of regulations and fire safety guidelines for commercial and residential building codes (see Calcium Silicate use in Europe). Where North Americans use spray fireproofing plasters, Europeans are more likely to use cladding made of calcium silicate. High-performance calcium-silicate boards retain their excellent dimensional stability even
Electrical insulation paper is made on small paper machines with slow speeds because the stock has to be drained very slowly. Transformer board is used mainly in oil-filled transformers where a solid insulating structure is needed. This is a pressboard up to 8 mm in thickness. The board is built up wet on forming cylinders and cut off when at the desired thickness. This makes a sheet with the size of the width and circumference of the drum. The wet sheets are hot- or cold-press dried and finished on separate machines. The use of paper board as electrical insulation paper started in the