Monitoring and Enforcement of Noise Threshold Compliance of Construction Noise near Residential Estates

3 Dr Charlene Chen asked the Minister for Sustainability and the Environment (a) in relation to construction noise near residential estates, how is compliance with noise thresholds enforced and how frequently is it monitored; (b) how are prolonged duration and cumulative exposure to such noise factored into enforcement measures; and (c) whether noise thresholds will be reviewed, including the use of psycho-acoustic factors such as sharpness and roughness of sound.

The Senior Minister of State for Sustainability and the Environment (Dr Janil Puthucheary) (for the Minister for Sustainability and the Environment): Mr Speaker, Sir, construction sites within 150 metres of residential premises are required to install noise meters which the National Environment Agency (NEA) monitors. NEA takes strict enforcement action against contractors who exceed the permissible noise levels, with more severe enforcement action typically taken for repeated offences as well as those with a longer duration of time above the permissible noise level.

NEA will continue to review the regulations including the permissible noise levels to ensure that they remain relevant and effective in protecting public health.

Mr Speaker: Dr Chen.

Dr Charlene Chen (Tampines): I thank the Senior Minister of State for his response. Residents in Tampines living near the long-running Loyang Viaduct construction have reported prolonged stress from construction noise. So, given that sounds of similar decibel levels can differ in perceived loudness and distress, does the Ministry consider the use of psycho-acoustic factors, such as sharpness and roughness, in the review of thresholds?

And another supplementary question would be what are the penalties when construction sites exceed noise thresholds?

Dr Janil Puthucheary: Sir, I thank Dr Charlene Chen for her questions. When it comes to psycho-acoustic factors, we take reference from the World Health Organization (WHO) guidelines, which currently do not include psycho-acoustic factors, but this is a part of the science that is under review. We will continue to review our stance as well as take reference from the WHO with respect to what are the factors of sound that we take into account when enforcing the framework.

Dr Chen also asked about the penalties. There are different ways in which we do this. The requirement for monitoring itself is a burden placed on the site operator, potentially requiring closed circuit television (CCTV), continuous real time monitoring. But if they transgress, then we will take further action against them. And if they fail to comply with the regulations, they will be guilty of an offence and shall be liable on conviction to a fine not exceeding $40,000. In cases of continuing offences, further fines not exceeding $1,000 a day, or part thereof, during which the offence continues after conviction. Thereafter, there are composition sums, depending on the circumstances of the case and the court findings.

Mr Speaker: Ms Gho Sze Kee.

Ms Gho Sze Kee (Mountbatten): Similar to the hon Member, Dr Chen, I also receive feedback from residents of RiverEdge, a condominium that is situated in Tanjong Rhu. The lived experience on the ground appears to differ materially from what average equivalent continuous sound level (LEq) measurements suggest, with the Tanjong Rhu Build-To-Order construction site located less than 150 metres of existing residential block, residents have informed me that these repeated short bursts of intense construction noise that are technically compliant when averaged over five minutes – but nonetheless, they are quite disruptive.

So, I have two questions for the Senior Minister of State. In such close proximity situations, how does NEA assess whether the current averaging based approach adequately reflects the actual disturbance experienced by the residents? And will the Ministry consider using Lmax instead in assessing compliance and addressing residents' complaints?

Dr Janil Puthucheary: Sir, I thank Ms Gho for her questions. Indeed, we will consider and review how to best provide the correct supervision, regulatory framework and enforcement. We need to have a balance between the protection of the public health and allowing necessary work to proceed.

And indeed, we do have an averaging of five minutes, but we also have some of the framework where it is averaging over 12 hours.

So, there is a balance that we need to strike for different types of sound: persistent recurrent, repeated sharp bursts, as Ms Gho has pointed out. The current framework requires an average sound level over five minutes and she has asked us about Lmax, which means, not taking into account the time span for a person to be exposed to that sound, but the absolute level for the sound exposure. It is indeed something that we can study and we will study together with taking reference from the WHO guidelines that I explained earlier, which is the basis on which we have developed our framework. And this is also something that is under study internationally.