Good Practices on the Control of Noise from Electrical & Mechanical Systems



Under the Noise Control Ordinance, noise generated from activities carried out in industrial or commercial premises should comply with the noise standards as stipulated in the relevant Technical Memorandum. It is generally recognized that operation of electrical & mechanical systems, such as ventilation systems, pumping systems, lift systems and emergency generator sets, is one of these noisy activities. This website highlights the importance of planning against noise problems. It gives a brief description of potential noise problems associated with electrical & mechanical systems and provides guidelines on practical noise control measures that are applicable for new designs and for retrofitting existing designs.

The reader should note that compliance with the recommendations of this website does not necessarily mean compliance with the legislative requirements. Besides, the recommendations made in this website are not exhaustive. Alternative solutions to achieve the same results may exist. The reader is therefore advised to consult independent experts* for ensuring the use of proper and cost-effective noise control measures. 

This website is designed mainly for assisting restaurant operators, building operators, building management, incorporated owners, and contractors to better understand noise control knowledge in relation to the operation of their mechanical & electrical systems and hence adopting the most appropriate mitigation measures where necessary. Architects, building services engineers or other relevant professional parties may also use it as a checklist to ensure that proper measures will be taken to avoid noise problem in designing electrical & mechanical systems and locating equipment. The main contents are written in plain language illustrated by schematic diagrams for easy understanding by a layman. The focus is on practicable measures. More technical information can be found in appendices.


Remark(*):  The Hong Kong Institute of Acoustics Limited has provided a list of the corporate members showing interest in rendering acoustic consultancies and noise measurement services. For details, please visit the link below: You may also approach the Registered Engineer Board (website: or other professional institutes such as The Hong Kong Institute of Qualified Environmental Professionals Limited for the list of relevant professionals.