Building insulation materials is used depends on a wide variety of factors. Some insulation materials have health risks, some so significant the materials are no longer allowed to be used but remain in use in some older buildings such as asbestos fibers and urea. Factors affecting the type and amount of insulation to use in a building include: Considerations regarding building and climate: Often a combination of materials is used to achieve an optimum solution and there are products which combine different types of insulation into a single form. Spray foam is a type of insulation that is sprayed in place through a
Electrical insulation paper Electrical insulation paper Electrical insulation papers are paper types that are used as electrical insulation in many applications due to pure cellulose having outstanding electrical properties. Cellulose is a good insulator and is also polar, having a dielectric constant significantly greater than one. Electrical paper products are classified by their thickness, with tissue considered papers less than 1.5 mils (0.0381 mm) thickness, and "board" considered more than 20 mils (0.508 mm) thickness. The more demanding application the cleaner the paper needs to be. Paper machines are run with deionised or even distilled process water when producing higher grades of electrical