Radiation monitoring equipment for accident and post-accident conditions in nuclear power plants. Part 2: Equipment for continuously monitoring radioactive noble gases in gaseous effluents

This standard is applicable to the monitoring of radioactive noble gases in gaseous effluents from nuclear power plants in accident and post-accident situations. The monitoring process is specified and some general principles are given concerning the sensitivity and monitoring range of the equipment serving to provide information on radioactive gas leaks as a basis for protective measures. The standard does not apply to conventional sampling and laboratory analyses within the normal effluent monitoring programme; instead, it is applicable to noble gas effluent monitors designed specifically for accident and post-accident monitoring of (i) the volume activity of radioactive noble gases in gaseous effluents at the site of their release into the environment, and (ii) volume activity changes in time. The monitors can also be used to determine the total released activity of noble gases over a predetermined time interval. Requirements are laid down, put on the equipment for continuous noble gas monitoring in gaseous effluents in accident and post-accident conditions. (Z.S.)