Lockout Tagout, or LOTO for short, is a familiar term to many. It serves to prevent accidents during maintenance work. LOTO prevents a machine or system from being energized while maintenance work is still being carried out and protects workers from the dangerous energies inherent in the machine. In the USA, the use of LOTO is required by law. In Germany, more and more companies are increasingly relying on this principle to prevent accidents.
However, LOTOTO is now being mentioned more and more often. The second TO stands for “tryout” – checking whether the machine is actually de-energized. This is an important point, as the LOTO(TO) instruction may also be incorrect or someone may simply have forgotten to close a main switch or ball valve. In such a case, the machine would react in some way during the functional test and corrective action could then be taken.