What type of water source is used when determining the rated capacity of a pump?

When determining the rated capacity of a pump, the appropriate water source to consider is a draft source. This involves drawing water from a static water source such as a lake, pond, or cistern. The rated capacity typically refers to the pump's ability to draw water from these sources efficiently.

Using a draft source is crucial because it helps to assess the pump's performance under real-world conditions where it may need to pull water from a non-pressurized source. This evaluation reflects the pump's true capacity and operational effectiveness, particularly in firefighting scenarios where direct connections to municipal supplies or hydrants are not available.

In contrast, while municipal supply, static water sources, and hydrant flow may be relevant to overall water supply considerations, they do not specifically relate to the determination of the pump's rated capacity in the context of drafting operations. Therefore, the focus on draft sources highlights the pump's ability to function optimally when tasked with lifting water, which is essential in many emergency situations.