A radioactive cloud released into the atmosphere from the stack of a nuclear facility may cause direct or indirect exposure on the public around the site through some pathways.
In this report are outlined the so-called general Gaussian formula with F. Pasquill's data for radioactive concentration distribution in the cloud, submersion model for β and γ exposure to the cloud and direct calculations of cloud γ exposure, radioactive deposition on the ground, and others. The estimation by A. Adams of whole body γ dose which was used in H. J. Dunster's assessment of 85Kr dose is questioned. A calculation method of annual population dose arround a site under normal operation condition is mentioned. Meteorological condition assumed in safety analyses for emergency are discussed by taking examples of U. S. AEC Safety Guide 3 and 4 as well as the guide in Japan.
