The contamination of any material, surface, environment or person by radioactive substances such as alpha particles or gamma rays. Radioisotopes used in industry (e.g. medicine, food, pasteurisation) are generally of low power with a short life. The risk is insurable if the UK’s Atomic Energy Authority standards for the use of radioisotopes are strictly observed. Product and public liability policies exclude loss or damage from ionising radiations or contamination from any nuclear fuel or waste from the combustion of nuclear fuel. See NUCLEAR PERILS.