Noise in conditioning installations

Abstract

This article gives a general account of the noise problem in air conditioning systems. This problem causes grave concern to the technicians owing to its influence on the comfort of the buildings concerned. The acceptable levels of noise are discussed, also their codification into general specifications. Methods are given to test whether a given installation satisfies such noise specifications, and the means that are usually adopted to prevent air conditioning noise from extending into inhabited rooms. The study of the limitation of noise to a comfortable level depends both on the noise specifications and the actual design of the installation. Scale «A» is utilised in connection with the specifications, and the sound spectral curves are part of the design technique, which enables to obtain the cheapest design for the same level of comfort. The designer needs the fullest cooperation of the manufacturers, who should supply him with detailed accoustical data about the equipment. This applies both to installations that will produce noise and to the material that is meant to absorb it.