When not in use, an adjustable nozzle should be set to what position?

The correct answer is the fog position. Setting an adjustable nozzle to the fog position when not in use serves several important functions. First, this position allows for the nozzle to be ready for quick deployment if an emergency arises, as fog patterns can be rapidly adjusted for various situations, providing versatility in firefighting efforts. Additionally, in the fog position, the nozzle can help prevent damage or leaks, as it ensures that water isn't continuously flowing through the nozzle when it's not actively in use.

Choosing the fog position also maximizes safety. When the nozzle is set in this way, it can reduce the risk of accidental discharge of water that could lead to safety hazards or unintended consequences while the apparatus is in transit or when personnel are preparing for an incident.

Other positions, like stream or wide, may not have the same benefits when the nozzle is not actively deployed since they could potentially lead to water running through the system unnecessarily, increase wear on the equipment, or create confusion among the crew about the readiness of the nozzle for immediate use. Therefore, fog position is the most prudent choice when the nozzle is not in use.