When attacking fires in bowstring or lightweight truss assemblies, which area is prioritized?

Prioritizing the attack on fires in the upper portions of bowstring or lightweight truss assemblies is crucial due to the inherent risks these structures present. Bowstring trusses are known for their potential to fail quickly under fire conditions, and the materials used in lightweight truss systems can contribute to rapid fire spread. When a fire begins in these areas, it can compromise the structural integrity of the trusses, leading to possible collapse.

By focusing on the upper portions of the truss, firefighters can effectively combat the flames that are directly threatening the structure and prevent the fire from spreading further. This approach also allows for better control of the fire from a tactical standpoint, as attacking from above can help to cool down the fire and limit its ability to grow. Addressing the source of the fire as it moves up within the truss system is key to ensuring the safety of both the occupants and the firefighting teams, as well as preserving the building's structural integrity as much as possible.