This document:specifies methods for the measurement of airborne and structure-borne sound produced in waste water and rain water installations under laboratory conditions;defines the expression of the results.It is applicable to waste water piping systems and parts thereof, but not to the actual sources of the wastewater, e.g. lavatories, toilets and bathtubs or any active units. It applies to pipes with natural ventilation and made of any common material in commonly used diameters (up to 150 mm).The results obtained can be used for the comparison of products and materials. It may serve in estimating the behaviour of waste water systems in a building under