The supply airflow through the subfloor plenum is the foundation of any cooling program. Inconsistent supply due to high velocity prevents cooling air from getting to the computer intake especially at the top of the rack. A balanced supply volume is essential in order to match the kW load in each cabinet.

The SubZero velocity adjustor is designed to lower velocity in the subfloor so as to eliminate low pressure areas that form due to an effect known as the Bernoulli principle. Another low-pressure problem that is eliminated is subfloor eddies that are formed when two high velocity currents of air meet in the subfloor. Slowing the air increases pressure. This in turn creates a consistent supply of air to any part of the data center.


SubZero products have independently been tested by the FM Global Research Test Center. This was at the request of one of our potential customers. Below are the results of that test. The FM Global Research Test center has completed testing on the SubZero product. Here is a synopsis of test results: "The extremely low heat content and very high percentage of inert material on both the outer material and inner pillow material is indicative of the very limited combustibility of this product. Parallel panel and random burn testing did not result in any self propagation of flame spread across the surface of the materials tested. With the presence of the Halon system in the sub floor for fire suppression, it is not expected that the introduction of these cubes adds any significant level of combustibility or presents any other fire hazard to be concerned with."

Made of Sandel
The Fire Fighting Fabric

SubZero velocity adjustors are made of ‘Sandel’. Sandel is called ‘the fire fighting fabric’. Sandel is an intrinsically non-flammable material, created to stop fire from spreading. Sandel will not ignite or burn. Sandel will not melt, drip, rot, or shrink. The principal ingredient in Sandel is silica or sand.

Designed to meet:

California TB 133

NFPA 258

NFPA 701 (UL-214) Small scale

University of Pittsburgh Smoke toxicity test “A” rating

British Standard 5852/4