What is the maximum theoretical lift for drafting?

The maximum theoretical lift for drafting typically is around 34 feet, which is rooted in the physics of atmospheric pressure and the properties of water. At sea level, atmospheric pressure can support a column of water up to approximately 34 feet. This is governed by the principle that as atmospheric pressure pushes down on the water, this force must be overcome by the suction generated by the pump to lift the water.

In practical terms, while one might achieve the ideal 34-foot lift under perfect conditions, various factors such as air temperature, water temperature, and the presence of any obstructions can reduce this lifting capability.

Understanding this theoretical limit is critical for firefighters and fire apparatus engineers when designing and operating draft systems, as it affects how effectively they can obtain water from sources such as ponds or hydrants when traditional supply lines are not feasible.