Flue Space Between Palletized Products Inside Storage Racks

Imagine this:
A warehouse fire starts at the bottom of a pallet rack system. In a matter of time, the overhead sprinkler kicks in. The storage system is 12’ tall, with two beam levels and a floor level. Each level has two pallet positions on a 96” (8’) long load beam, and 42” wide pallets.

In order for the sprinkler to be effective, the flue space between the loads needs to be wide enough for the water to reach the fire. When designing pallet rack applications, horizontal flue space is one of the key factors to make storage racks work efficiently with sprinkler systems and meet fire codes. Typically, most fire codes require that there is 3” of horizontal flue space and 6” of longitudinal flue space between the loads, as well as 18” of space between the sprinkler and the loaded rack.