Which statement about resupply servicing rules is correct?

• A. Foam hatch should be closed when pumping
• B. Water fill is never performed using hydrants
• C. Auxiliary agents may be mixed to increase efficiency
• D. Water fill may use hydrant/mobile supply/supply line/overhead fill

Answer: (D)

Resupply servicing rules specify how water and firefighting agents are replenished to sustain operations, ensuring a continuous and safe supply to the apparatus. The statement that water fill may use hydrant, mobile supply, supply line, or overhead fill reflects the practical, allowed methods for replenishing water in the field. Hydrants provide a reliable, high-flow refill when available. Mobile supply units bring water to scenes or stations where hydrants aren’t convenient, keeping units topped up. A supply line can deliver water directly from a fixed or mobile source to the vehicle, useful for extended operations or remote locations. Overhead fill uses an elevated or gravity-fed source to speed up replenishment when ground access is limited.

Other options describe procedures or capabilities not directly tied to replenishment sources: foam hatch status during pumping is a procedural detail of the foam system, hydrants being never used contradicts standard practice, and mixing auxiliary agents to increase efficiency falls outside the basic water resupply methods covered by these rules.