Fire Safety Science Digital Archive

An experimental model branchpipe, with a capacity of 5 l/min (1.1 g/min) of liquid, was used to investigate how the branchpipe configuration affects performance. The expansions, 25 per cent drainage times, shear stresses, and jet throws, of the foams were measured. A representative range of foam liquids was used and concentration and supply pressure varied. Some principles of design were determined. The model was compared with larger branchpipes. A specific design for a 5 l/min branchpipe, which is simple to construct, and has good characteristics, is described. NOTE. This branchpipe could be used as a laboratory reference standard and for the convenience of those who may wish to use it for this purpose, engineering drawings and a recommended test procedure, are being issued as a separate Fire Research Note No.971