Use portable electrical appliances in general places and install leakage protectors with rated electric shock current not greater than 15mA and rated operating time less than 0.1 seconds. If class I electric hand tools are used, they must also be connected to zero protection, and operators should wear insulating gloves , wear insulating boots or stand on insulating mats.
When operating in a wet place or on a metal frame, use Class II hand-operated power tools and install anti-splash guards. Use of Class I hand-operated power tools is strictly prohibited.
Narrow places (boilers, metal containers, trenches, pipes, etc.) must use a Class III hand power tool with an isolation transformer; if a Class II portable power tool is selected, it should be equipped with a splash guard, isolation transformer or leakage protector It is installed outside a small place and should be supervised when working.
The load wire of the hand-held power tool must be a weather-resistant rubber-coated copper core wire, without joints, and it is forbidden to use fancy plastic wires.
Grinding wheels that are damp, warped, cracked, broken, knocked or chipped or exposed to oil and alkali should not be used. Wet grinding wheels should not dry themselves. Grinding wheels and floppy disk pads must be installed firmly, and nuts should not be too tight.
Before doing your homework you should check:
(1) The shell and handle must be free of cracks or damage;
(2) The zero-protection connection must be correct, firm and reliable, the power cord and plug must be intact, the switch action must be normal, and attention must be paid to the switch operation method;
(3) The electrical protection device is good and reliable, and the mechanical protection device is complete

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