Which performance test requires a discharge hoseline from a second pumper?

The performance test that necessitates a discharge hoseline from a second pumper is related to the internal intake pressure relief valve test. This specific test helps verify that the pressure relief valve functions correctly under operational conditions by allowing the flow from a different source.

During this test, a secondary pumper provides additional water flow, which is crucial for creating the necessary conditions to assess the performance of the internal intake pressure relief valve adequately. This setup helps monitor how the valve responds when subjected to varying pressure scenarios, ensuring it opens and closes properly in real-world situations, ultimately contributing to operator safety and equipment reliability.

In contrast, the other tests focus primarily on different aspects of the pumper’s functionality without requiring a discharge hoseline from an external source. For example, the discharge pressure gauge and flowmeter operational tests measure the pump’s capabilities at specific settings without needing a second pumper. Similarly, the priming system test assesses the pump's ability to draw in water, and the tank-to-pump flow test observes water transfer from the tank to the pump, both of which do not rely on a secondary flow source for completion.