The tests were conducted in accordance with the procedures specified in BS476 Part 24 1987. Two small unit attenuators and a large unit splitter were tested and each unit achieved 61 minutes integrity.

On completion of the tests the specimens were examined and were found to be free from cracking and distortion.

Duct Silencers are typically located in ducts that, in the event of fire, may be required to deliver fresh air to people in the building or to exhaust smoke from the fire affected area. It is critical that duct silencers in fire conditions do not collapse and obstruct the duct.

To assess the capacity of Mason Sound Lock Silencers to resist collapse in fire, a series of fire tests were conducted on silencers and splitters at Internationally recognized Warrington Fire Research Melbourne Australia

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