IS & Ex

AST Africa introduces Whisp-Air

August 2015 IS & Ex

Today, many hard disk drives are designed and produced in China with little to no vibration testing. This has created something of a problem when one considers the potential vibration damage that could result when a gaseous fire extinguishing system discharges a data centre. Noise issues, and the vibration damage associated with these, have been attributed to all gas types, and IT specialists need to investigate specific measures that can be implemented because as the mechanical disk drives become more sensitive due to performance and cost objectives, this problem will only get worse.

However, for the interim, Alien Systems & Technologies has developed and manufactured a product that will treat the symptoms and lower the risk of damage to hard disks. The Whisp-Air Silencer Nozzle has been designed specifically for use in applications where protection of sound sensitive equipment such as hard drives is required.

The Whisp-Air’s full-flow design uses interposing sound waves, multiple-stage velocity deceleration, an obstruction-free expansion chamber and a metal fibre disseminator to dissipate potentially damaging discharge noise. A large peripheral exhaust surface area diffuses the extinguishing media, further lowering its velocity and reducing discharge noise.

The Whisp-Air silent nozzle product eliminates excessive discharge noise by dividing the extinguishing media stream and turning it back on itself. As the extinguishant enters the muffler at high velocity, it is redirected into smaller streams that rebound off opposing walls of the chamber. When these steams collide head-on with each other, the velocity is reduced and the extinguishant is dispersed throughout the large exit surface area. This technique eliminates noise without sacrificing flow rate or increasing back pressure.

For more information contact Samantha Wright, Alien Systems & Technologies, +27 (0)11 949 1157,,


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