What is a primary disadvantage of using exhaust primers in firefighting operations?

The primary disadvantage of using exhaust primers in firefighting operations is that they can have low efficiency. Exhaust primers function by using the engine's exhaust to create a vacuum that draws water into the pump from the supply source. This process can be less efficient compared to other priming methods, such as electric or manual primers, particularly under certain conditions, like high temperatures or with certain types of water supply. The low efficiency might lead to slower priming times, which is critical during firefighting situations where every second counts.

In contrast, options related to increased fluid pressure, low power output, and high maintenance requirements do not primarily capture the essence of exhaustion primer disadvantages. While there may be maintenance considerations or limitations on power output in specific scenarios, the most significant drawback lies in their efficiency during the critical moments of operation.