What is always required before performing maintenance work on any mechanical or electrical equipment?

Lock out/tag out is a crucial safety procedure that must be followed before performing maintenance work on mechanical or electrical equipment. This process involves isolating the energy sources of the equipment and locking them in a safe position to ensure that the machinery cannot be inadvertently powered on while maintenance activities are ongoing. The purpose of this practice is to protect workers from accidental start-up, which can lead to serious injuries or fatalities.

By implementing lock out/tag out, maintenance personnel are able to work on equipment without the risk of being exposed to hazardous energy, whether it be electrical, mechanical, hydraulic, or otherwise. This protocol not only enhances safety but also promotes adherence to regulatory standards that aim to protect workers in industrial settings.

The other options, while important aspects of safety and maintenance, do not specifically address the critical action necessary to prevent accidental activation of equipment during maintenance. For example, notifying a supervisor or wearing personal protective equipment are good practices but do not provide the direct safety control that lock out/tag out establishes. Disconnecting all power sources is related, but without the lock out/tag out system, there's no guarantee that power will not be restored accidentally. Thus, lock out/tag out stands out as the foundational step before any maintenance work begins.