The evolution of safety in the context of maintenance activities has generated a series of new products, among which the LOTO (Lock Out Tag Out) range has had great success.
Such products have been wrongfully considered an alternative to interlocks for a long time. However their function in the safety maintenance is to isolate the single apparatus and communicate the running maintenance intervention, therefore LOTO is not capable of defining any sequence of actions, and the responsibility of the correct application of the safety procedure falls totally on the operator.
On the contrary, the LOTO range represents an useful integration to the interlocking system, introducing a new key variable: the capability to govern multi-accesses, typical aspect of the outsourcing of maintenance processes, with the multiplication of the operators working at the same time.
In this sense, LOTO becomes an element integrated with the interlocking system, developing a multi-access logic that allows the safety of the whole maintenance process until the last worker has finished his operations.