Air Handling Ducts

A calibration run is made with asbestos cement board, which represents a 0 

The smoke results are calculated by determining the area under the light absorption versus time curve, dividing by the light absorption versus time curve obtained using red oak as a standard material, and multiplying by 100. 

Overall, the tunnel test is conceptually simple, provides a large enough surface area to simulate a real fire, and gives reasonably reproducible results. 

All laminates consisted of 1 ply C-glass veil and 2 plies of chopped strand mat followed by 1 ply C-glass veil.  

Reproduced with permission from W.H. Julius in Proceedings of the Composites Institute 45 Annual Conference, Washington, DC, USA, 1990, Paper No.2-D. 1990, Composites Institute [23]  

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The use of an air-handling duct system to return air from the interior of a building to the air-handling unit. 

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