When using MWS apparatus, one disadvantage of the direct pumping method is

When using MWS apparatus, one disadvantage of the direct pumping method is

• A. A constant water supply cannot be maintained
• B. It requires less equipment
• C. It minimizes priming time
• D. It reduces energy use

Answer: (A)

Direct pumping with a Mobile Water Supply relies on drawing water straight from an external source into the pump. Because no water is stored onboard to buffer demand, the flow you can deliver depends entirely on the external source’s ability to supply water. If hydrant pressure drops, flow is insufficient, or the source runs dry, you can’t guarantee a steady, continuous supply to the fire lines. That’s why the main drawback is the inability to maintain a constant water supply. The other options describe potential advantages (less equipment, shorter priming, lower energy use) and aren’t describing a drawback of direct pumping.

Direct pumping with a Mobile Water Supply relies on drawing water straight from an external source into the pump. Because no water is stored onboard to buffer demand, the flow you can deliver depends entirely on the external source’s ability to supply water. If hydrant pressure drops, flow is insufficient, or the source runs dry, you can’t guarantee a steady, continuous supply to the fire lines. That’s why the main drawback is the inability to maintain a constant water supply.

The other options describe potential advantages (less equipment, shorter priming, lower energy use) and aren’t describing a drawback of direct pumping.