Only welders are allowed to perform welding work

The main events leading to the accident:

A, without wearing a safety belt or taking other safety measures, climbed onto the roof truss to replace welder B, welding the angle steel and rebar supports of the roof truss in the workshop. After working for one hour, assistant worker C went down to retrieve the angle steel material. Since there was no assistant, A supported the rebar to be welded with his left hand, held the welding pliers in his right hand, and operated with his eyes closed. At that time, welder A fixed one end of the rebar, then leaned forward to weld the other end, still holding the fixed end with his left hand. Just as A closed his eyes, the rebar he was holding, due to its unstable fixing point, could not support his weight and suddenly detached from the weld. Welder A, along with the rebar, fell from the 12-meter-high roof truss and died instantly.

The main causes of the accident:

(1) A was not a professional welder.

(2) There was no supervisor at the work site when the accident occurred.

(3) The worker working at height did not use a safety belt or other safety facilities.

What are the main preventive measures?

(1) Non-professional welders should not engage in welding and cutting operations.

(2) A professional supervisor must be present for any work at height.

(3) Standard fall arrest harnesses must be used for any work at height, and safety nets and other safety facilities must be in place.