What is the primary purpose of using a horizontal flow of water over a hatch during a fire?

Using a horizontal flow of water over a hatch during a fire primarily serves to remove smoke from the area. This technique helps to clear smoke, allowing for better visibility and safer conditions for firefighting efforts and evacuation if necessary. By directing water across an opening, the flow can help to push the smoke away from the area, making it easier for personnel and equipment to operate effectively. Additionally, this method can assist in cooling the space, which is often a crucial aspect during fire suppression activities.

While other options relate to fire control, they do not specifically describe the purpose of directing water horizontally over an opening in the same way. For instance, extinguishing flames focuses on directly eliminating the fire, rather than facilitating visibility and air quality. Creating a barrier against smoke is more about preventing its entry, and increasing humidity, while potentially having some benefits, does not directly address smoke removal in the context of firefighting.