The type of fog nozzle that maintains approximately the same nozzle pressure even if the gallonage supplied to the nozzle changes is known as a(n):

An automatic nozzle is designed to maintain a consistent nozzle pressure across a range of flow rates, allowing for efficient firefighting operations. This nozzle automatically adjusts its orifice size to match the flow of water being supplied to it, ensuring that the pressure at the nozzle stays relatively constant. This is particularly advantageous when the water supply varies, as it allows firefighters to maintain effective stream performance without needing to manually adjust the nozzle.

In contrast, a variable nozzle may allow for changes in the stream pattern or flow rate, but it does not guarantee that the pressure remains constant with changes in the gallonage supplied. A fixed nozzle has a set pattern and flow rate with no adjustment capability, while an adjustable nozzle allows for manual changes in the flow or pattern but lacks the automatic pressure regulation of an automatic nozzle. Thus, the automatic nozzle's ability to consistently manage pressure contributes to its effectiveness in adapting to fluctuating water supply conditions during firefighting operations.