Which of the following is NOT a use of hose streams?

The correct choice highlights that shortening the duration of structure fires is not a primary use of hose streams. Hose streams are primarily tools for controlling and extinguishing fires, but their function is more about managing the fire and addressing its direct impacts rather than explicitly reducing the overall duration of a fire incident. Each of the other options represents important tactical applications of hose streams:

• Flushing flammable liquids and gases helps to mitigate hazards by moving these dangerous substances away from ignition sources.

• Controlling toxic fumes from chemical leaks is critical for safeguarding the health of firefighters and anyone in the vicinity, making it a significant application of hose streams.

• Protecting exposures from spreading fire is essential to prevent the fire from spreading to nearby structures or materials, showcasing the effectiveness of hose streams in safeguarding lives and property.

In summary, while hose streams play a role in impacting the course of a fire incident, their primary functions are not centered around the duration of the fire itself, but rather on fire suppression, risk mitigation, and exposure protection.