Calcium silicate used as an anticaking agent in food preparation, including table salt and as an antacid. It is approved by the United Nations' FAO and WHO bodies as a safe food additive in a large variety of products. It has the E number reference E552. Calcium silicate is commonly used as a safe alternative to asbestos for high-temperature insulation materials. Industrial-grade piping and equipment insulation is often fabricated from calcium silicate. Its fabrication is a routine part of the curriculum for insulation apprentices. Calcium silicate competes in these realms against rockwool and proprietary insulation solids, such as perlite mixture and vermiculite
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