The principles of performing prophylactic medical examinations of workers are regulated by the Labor Code and relevant executive regulations. There are also other regulations that concern particular groups of workers--like health care workers. The range and frequency of medical examinations are determined by the doctor who performs the examination on the basis of "Guidelines on prophylactic medical examinations of workers". Before determining the range of medical tests, the risk of occupational exposure to biological hazards in some of health care workers must be taken into account. This article presents legal regulations that determine the standards of prophylactic medical examinations of workers who are at risk of contracting pathogens such as HBV, HCV and HIV.