Collective dose scenario at MAPS - a fifteen year experience

Madras Atomic Power Station - a two unit PHWR- has provided a large data based on occupational exposure since 1983. ICRP-1990 recommendations have forced ALARA practices to be implemented seriously at MAPS to put a check on collective dose. In this paper, an analysis of collective dose has been made with fifteen years of experience in background (1983-97). The distribution of collective dose among different groups shows definite trend over the years. Focus has been made to identify the critical work group, critical jobs, critical work areas, critical radionuclides and the critical systems vis-a-vis the collective dose. Distribution of dose is off-centered, resulting in selective groups (casual workers, mechanical and operation) getting more than sixty percent of station dose and therefore these groups require special focus on dose reduction strategies. There is a reduction in collective dose by a factor of 2 to 5 in different jobs due to refining work procedures and other ALARA efforts. (author)