A verification system is implemented to ensure the continued isolation and de-energization of hazardous energy sources during the course of maintenance and servicing operations. Once the equipment is shut down and the hazardous energy has been controlled, maintenance/servicing personnel, sometimes in conjunction with operations personnel, must test the machinery or equipment to verify that the isolation of the equipment’s energy source(s) is effective. The employees may walk through the affected work area to verify isolation. If there is a potential for releasing or re-accumulating hazardous energy, verification of isolation must be continued.
OSHA has accepted an alternative to the individual employee verification requirement where complex LOTO operations involve many employees and numerous energy-isolating devices. In such situations, the employer may designate a primary authorized employee, with the primary responsibility for a set number of employees working under the group LOTO device(s). The primary authorized employee must implement and coordinate the LOTO of hazardous energy sources and verify that the steps taken, in accordance with the specific energy control procedure, have, in fact isolated the machine or equipment effectively from the hazardous energy sources. This must be accomplished before individual authorized employees participating in the group LOTO affix their personal lockout or tagout device to the group LOTO box and before they perform servicing/maintenance activities.
When a primary authorized employee verifies isolation, all authorized employees participating in the group LOTO must also be informed of their right to verify the effectiveness of the lockout measures. They must be allowed to personally verify that hazardous energy sources have been effectively isolated if they so choose. An authorized employee who opts to verify the effectiveness of the isolation measures must perform this verification after affixing his personal lockout or tagout device to the lock box and before performing servicing/maintenance activities.