How are types of pressurized ventilation categorized?

Pressurized ventilation is categorized by positive and negative pressure because these two methods represent the core operational principles used in various ventilation scenarios. Positive pressure ventilation involves introducing air into a structure, creating higher pressure inside compared to the outside. This technique helps to push smoke and heat out, improving visibility and conditions for firefighting and rescue operations. Conversely, negative pressure ventilation entails creating a vacuum effect, where air is drawn out of a structure, which can also assist in removing smoke and toxic gases.

The distinction between these two methods is crucial for firefighters to determine the most effective approach to use in different situations. Each method has its advantages depending on the conditions at the fire scene, the structure involved, and the objectives of the ventilation operation. Understanding the implications of using either positive or negative pressure allows firefighters to make informed decisions that can significantly enhance operational effectiveness and safety.