Final answer:
A quick-disconnect device must have a shut-off valve upstream for safety, to control flow and prevent leaks during disconnection.
Step-by-step explanation:
The statement that a quick-disconnect device shall require a shut-off valve upstream of it is true. This is a safety requirement in fluid and gas handling systems. The purpose of the shut-off valve is to allow for quick and safe disconnection of equipment without the risk of leakage or unwanted flow of substances, which could lead to hazards such as spills, fires, or explosions. Similar principles are applied to electrical systems, where high-voltage wires are connected to metal-frame towers using insulating connectors. However, contrary to the possible belief that these wires are individually wrapped in insulating material, they are actually bare, relying on the air gap and connectors for insulation.