Pay attention to the use of waterproof welding torch and waterproof cable for underwater welding, and use DC welding machine as welding power source instead of AC welding machine. Then, when welding, people avoid forming a loop between the positive and negative electrodes, and choose an underwater covered electrode that is not easy to get an electric shock, such as BROCO's EASYTOUCH underwater covered electrode. Because of the silver barrier layer and wax coating, it is waterproof and not electric shock on the premise of ensuring easy arcing.