Which operations would warrant the deployment of a master stream?

The deployment of a master stream is often warranted in defensive operations. This is because a master stream, which can deliver a large volume of water over a significant distance and usually from a fixed or aerial apparatus, is particularly effective for controlling large fires or where there is significant involvement of structure. In defensive situations, the goal is to protect exposures and prevent the fire from spreading, rather than aggressively attacking the fire directly.

When using a master stream defensively, it allows firefighters to create a barrier of water that can protect the surrounding structures, buy time for additional resources to arrive, and prevent fire from spreading to adjacent buildings or areas. This tactic is essential in instances where the fire is too large or unsafe to approach more closely, ensuring that efforts are focused on mitigation rather than direct confrontation with the fire.

While master streams can also be used in offensive operations under certain conditions, they are primarily associated with defensive firefighting, emphasizing the importance of understanding when to apply this powerful tool effectively.