Final answer:
The keys to the locks used in lock out tag out (LOTO) procedures should be held by the authorized employee who has applied the lock to ensure safety and prevent unauthorized attempts to restart machinery during maintenance or repair.
Step-by-step explanation:
When performing a lock out tag out procedure, which is a critical safety measure used in industrial and manufacturing settings, the keys to the locks should be in the possession of the authorized employee who applied the lock out device. The purpose of lock out tag out (LOTO) is to ensure that dangerous machines are properly shut off and cannot be started up again prior to the completion of maintenance or repair work. This is important to prevent accidental start-up of machinery which could cause injury or even fatality.
Each lock should have a single key, and it is that authorized employee who is responsible for the equipment's maintenance or repair that should retain that key. This procedure protects against unauthorized attempts to restart the equipment, ensuring that all energy sources are isolated and the machine remains inoperative during service or maintenance.