What limit is established for flapper-valve-type devices concerning product delivery shutdown?

The limit established for flapper-valve-type devices concerning product delivery shutdown is set at 95%. This percentage indicates the threshold at which the flapper valve is required to shut off the delivery of fuel or other products to prevent overflow and to ensure that the tank is not overfilled.

Achieving this 95% limit is crucial in maintaining safety and preventing environmental contamination that could arise from spills. The design of flapper valves ensures that they operate effectively within this threshold, allowing for a small buffer before flow is completely stopped. This specification is part of regulations to safeguard against accidental releases and to enhance operational safety within UST systems.

Understanding this limit is vital for those working with underground storage tanks, as it ensures compliance with industry standards and regulations designed for environmental protection and safety.