Longitudinal vs. Transverse Flue Space Dividers for Pallet Rack

Flue space dividers play a key role in warehouse fire protection and airflow management. Flue space refers to the vertical gaps between back-to-back pallet racks (longitudinal) and between adjacent pallets on the same beam (transverse). These dividers are typically made of wire or steel and help maintain those required clearances by keeping pallets from shifting into restricted areas. Maintaining these spaces is often required by fire codes, especially in facilities using ESFR sprinkler systems.

Longitudial Flue Space Divider (AKA WorldStops / Pallet Stops)

Longitudinal flue space dividers are used to keep a clear channel, often at least 6 inches wide, between rows of back-to-back racks. This channel allows heat and smoke to rise during a fire, which in turn helps activate overhead sprinklers. These dividers are installed vertically between rack frames and are important in high-density storage areas or automated systems, where pallet shifting is more likely and fire suppression is more complex.

Transverse Flus Space Dividers (AKA U-Dividers)

Transverse flue space dividers are installed on the same beam level between pallets, typically maintaining a 3- to 6-inch gap. Without these dividers, forklift operators might accidentally push pallets too close together, blocking the airflow needed for sprinkler systems to function properly. These dividers often clip onto wire decking and are helpful in operations dealing with various pallet sizes or frequent misalignment. They not only support fire code compliance but also improve picking accuracy by defining pallet positions more clearly.

Choosing the right flue space dividers depends on your warehouse setup, the consistency of your pallet loads, and the requirements of your local fire codes. Many facilities benefit from using both longitudinal and transverse dividers to ensure full compliance and maximize safety. In addition to fire protection, dividers help with air circulation, inventory visibility, and organization. With fire marshals and insurance providers increasingly requiring proof of clear flue space, installing dividers is a smart and great way to stay ahead of safety requirements.

At RackandShelf.com, we offer a variety of flue space divider solutions that are easy to install, compatible with wire decking, and designed to suit all standard pallet rack systems. Contact our team for a quote or consultation to make your warehouse safer and more efficient. We can help you find the right product for your specific needs.