ABOUT 20,000 construction workers involved in public works projects are to receive comprehensive safety training in a pioneering programme to be launched today by the Hong Kong Construction Association. The scheme aims to give site safety induction courses for all labourers and craftsmen working on government contracts. This is equivalent to a third of the total construction workforce. The association, which represents 350 construction firms, will issue green cards to trained workers. Following this there will be safety courses at each site to make workers aware of specific hazards. The association is also co-producing a safety manual.