What would you require for this bypass around a safety critical valve?
Temporary SOP, Car Seals or BOTH?
The automated valve is the Emergency Shutoff Valve tied to a Hi-Hi Interlock on an above-ground atmospheric flammable liquid storage tank. The LOPC/Over-Fill event occurred because the worker filling the tank was “shorthanded” that day and had to leave the unloading stations to attend to other unloading tasks around the facility. He knew the Hi-Hi interlock would stop flow into the tank. What he did not know was that the bypass around the emergency shutoff valve was OPEN.