Which condition should NOT lead to the use of PPV?

Using positive pressure ventilation (PPV) is an effective tactic in firefighting for managing smoke and heat, aiding in visibility and improving conditions for search and rescue. However, certain conditions can undermine its effectiveness or pose risks.

When there are strong winds against the exhaust opening, it creates an adverse environment for the application of PPV. The wind can disrupt the flow of air intended to push smoke and heat out of the structure, potentially causing backdrafts or pushing smoke into areas where it would otherwise be vented out. This can lead to increased danger for firefighters and victims inside the structure. In such scenarios, it's crucial to assess the wind patterns and adjust tactics accordingly, rather than relying on PPV, which may not be beneficial under those conditions.

In contrast, if the seat of the fire is found, it’s paramount to attack it directly rather than focusing solely on ventilation techniques. If the fire is under control, then the need for PPV diminishes because the dangerous conditions that PPV aims to alleviate are not present. Additionally, poor visibility due to smoke would usually warrant the use of PPV to clear the air for those operations, making this a situation where PPV is indeed appropriate.