NOISE GENERATED BY SIMULATED RAINFALL ON PROFILED STEEL ROOF STRUCTURES

A method is described, which conforms to the appropriate British Stand ard for measuring sound power, for determining the sound power radiate d from roof structures excited by water impact. Expressions are given for the dependence of the sound intensity level on the water impact ra te and the diameter and impact velocity of the water drops. A method o f estimating the A-weighted sound intensity level from natural rainfal l is derived based upon the measured results and the characteristics o f natural rainfall. Measured sound intensity levels are presented for sandwich-type roof claddings which illustrate some of the requirements for reducing noise generated by water impact.