insulation

views updated May 23 2018

insulation Technique for reducing or preventing the transfer of heat, electricity, sound or other vibrations. Wool, fibre-glass and foam plastic are good heat insulating materials because they contain air. This trapped air reduces the transfer of heat by conduction. Water is also a good heat insulator. A diver's wet suit keeps the wearer warm by trapping a layer of water around the body. Electrical insulation materials include rubber, PVC, polythene, glass and porcelain. Sound insulating materials absorb sound and change it to heat by friction.