The goal of the thesis was to study construction work safety. In the thesis topics studied were the history of work safety, differences between small and bigger con-struction sites, work safety in other fields, the safe usage of construction tools, construction work safety laws and regulations. Also the effects of asbestos, occu-pational diseases as well as demolition sites and explosion sites work safety were included in the study. The information for the thesis was gathered from the web pages of Centre for In-dustrial Safety and Occupational Safety Administration and also three books relat-ed to work safety.