Final answer:
The liquid percentage level at which the Type III hydrant system product recovery tank overfill valve will close depends on the specific design and specifications of the system.
Step-by-step explanation:
The liquid percentage level at which the Type III hydrant system product recovery tank overfill valve will close depends on the specific design and specifications of the system. However, in general, the overfill valve is designed to close when the tank reaches a certain liquid level to prevent overflowing. This level is typically predetermined based on the capacity and safety requirements of the system.
For example, let's say the Type III hydrant system product recovery tank has a capacity of 100 gallons. The overfill valve may be set to close when the liquid level reaches 90% of the tank capacity, which would be 90 gallons.
It's important to note that the exact liquid percentage level at which the overfill valve closes can vary depending on factors such as the specific system design, regulations, and manufacturer specifications.