TRADE union and work safety groups have called for a special safety code for lift workers, after three men were seriously injured in an accident this week. The Union of Lift and Elevator Employees and the Society of Registered Safety Officers also called for greater emphasis to be placed on safety when training lift workers. Society president Lee Hung-kwong said that though he was unaware of the details of Tuesday's accident, it was clear better safety precautions were needed. ''There needs to be a code of practice . . . to protect those who work on these lifts during maintenance because sometimes the working conditions can be dangerous,'' Mr Lee said yesterday. ''It should be developed together with the Government, professional bodies, engineers and the workers.'' One requirement could be that workers wear safety harnesses whenever they worked on the roof of a lift. The injured maintenance workers were standing on top of the elevator when it fell several storeys to the ground at a Shau Kei Wan building.