(Writing in english due to handwriting pad failed)
It is very danger to let those non-REW working on Live parts as they have no responsible (in Law) on what they do. Especially those so call skillful worker and so call specify talent who came from Main Land China (in my experience). The REW on site (or in-charge) will be suit on court under criminal in case accident happen. So the REW must isolate all Live parts, and lock the faculty if possible, before ask his non-REW subordinate to do something.
Many site worker say ** No accident - ke ke ke; Accident happen - finish !! ** to warn those apprentices and new hands.
參考: I am a group leader of electrical maintenance in a large public utility.