LOTO stands for Lockout/Tagout.  It is in order to prevent the workers from the danger caused by the machine start accidentally, the equipment launch abnormal, the energy source release when the worker wants to repair or maintain it. So that it can keep the worker's personal security. The key of LOTO is to cut off the connection between machine and power source, lock on the source, release residual power. When done properly before equipment service or maintenance, lockout/Tagout procedures control hazardous energy and protect workers from harm.