ABSTRACT
This paper reported the situation of radiation contamination in the environment after Chernobyl accident.50,500km2 of area in Ukraine were contaminated,and 10% of Ukraine residents were living in the contaminated region.The population exposed with radiation were categorized according to the 4 stages of the Chernobyl accident and the successive development,i.e.the earliest contaminated stage,the radioactive iodine contamination,radioactive residue contamination and the long-life radioactive materials contamination.The tasks of the armed forces and the major work of the logistical department were introduced.Medical measures,the dose-limit criteria for the professional people were established,and the related radiation safety and protection system were constructed for the implement of these measures and action.It was very important to take iodine tablet as early as possible for the members of rescue corps and residents to protect the thyroid,and to regularly inspect the food and water.With the adoption of the effective complex protective measures,these three important tasks had been achieved:further injuries to human from the contamination of immense radioactive materials was prevented,the internal exposure dose on the residents was decreased,and large scale contiguous diseases and food toxic event did not occur.