The whole body monitor of JAPC Tsuruga Atomic Power Station got started operation on Sep-7th, 1970. The number of measurements of workers reached 5101 on Dec. 31st, 1971. From these experiences, it became evident that whole body counting in routine monitoring is useful for both the improvement of working environment and the diminution of the cause of body contamination. The change in frequency distribution of the counting values of all the subjects suggests a change in the state of contamination control. This paper, moreover, referred to the screening level and procedure for whole body monitoring.