This part of EN ISO 3822 specifies the mounting and operating conditions to be used for on-line valves and appliances which control the flow, pressure or temperature of the water in water supply installations, when measuring noise emission resulting from water flow. It is applicable to in-line valves and appliances of maximum nominal size DN 32 and to systems in which the maximum water flow rate does not exceed 2 l/ s. The procedures described are for general use for all types of in-line valves of conventional design.