Finding the balance with urban and environmental acoustics
作者
Sound can both be healing and potentially impact on our health and wellbeing when it is unwanted and excessive. Urban evolution and our way of life have progressively resulted in changes in our environmental soundscape that may not always be positive.
When we think of unpleasant city noises, it’s the very loud and irritating ones that often spring to mind, such as crashes, banging, beeping, honking, sirens and shouting. But underlying these individual dissonant notes, there is also an all-pervasive background noise generated by a range of sources and this forms our ambient sound environment.
Fans, the compressors in refrigeration and air conditioning units, background traffic, pumps, boilers and diesel generators are all examples of such sources contributing to a blanket level of mechanical babble in the urban environment. Machinery and plant powering our industries, ever growing infrastructure paving the road for our progress, and urban expansions are other sources that are contributing to changes to general environmental soundscapes.
When these changes in soundscape are adverse (i.e. noise pollution), they can negatively impact on our health and wellbeing and have side-effects including sleep disturbance, irritability, difficulty concentrating and stress. They can also result in undesirable changes in our natural habitats and environment by impacting flora, fauna and associated ecosystems.
General Environmental Duty
We all have a General Environmental Duty to protect our One Planet and leave a legacy of sustainable and prosperous future. This is one of the reasons why environmental policies such as the new Victorian Environment Protection Act and General Environmental Duty (GED) seek to reduce all kinds of noise and promote and adopt a proactive approach in minimising impact to our environment, maintaining a suitable ambient soundscape.
The GED means every business and individual must do their part to ensure their activities do not cause harm to people or the environment due to waste or pollution. Noise falls under the category of pollution, and the onus is on every business and every asset owner to ensure noise is managed to levels that are as low as reasonably practicable (ALARP). It is very important to understand that GED is going beyond what is required to prevent noise pollution and is proactively engaging to improve our environment by ensuring noise emissions are ALARP.
GED requirements are enforceable through relevant state Environmental Protection Acts and subsidiary legislative frameworks which apply to both new and existing developments or enterprises. New developments should therefore engage an acoustic consultant at the earliest stage possible (e.g. site due diligence and planning) to enable appropriate consideration of such impacts. The reality is that as we densify our cities and create more mixed-use hubs where residential, commercial, retail and industrial premises are co-located, issues of noise become more acute.
“The General Environmental Duty (GED) means every business and individual must do their part to ensure their activities do not cause harm to people or the environment due to waste or pollution.”
There may be sites where the use and functionality a developer is imagining – such as an advanced manufacturing facility, a major hotel with a nightclub, or a logistics facility – will be extremely difficult or cost prohibitive to deliver in a manner that achieves the objectives of ALARP. An acoustics analysis before deciding on the site is therefore critical to the business case.
Additionally, quite often there may be strategies that could be easily integrated into the project at early stages such as land use control or integrating site features for noise transmission control. These can have notable acoustic benefits compared to other solutions later in design or operational stages, steering the project towards ALARP objectives on a more cost-effective path.
If the business case and feasibility stack up, then acoustics is engaged as design progresses to embed noise management and abatement for both the construction process and the operational phase of the asset ahead of seeking development consent. Then we – as acousticians– stay involved through construction and commissioning to enable the final acoustic outcome achieving client vision, meeting the needs of occupants and the surrounding community for a pleasant acoustic environment while compliance with the relevant environmental requirements and obligations are achieved.
Overall, activity hubs are a new challenge for our industry from an acoustic perspective, particularly when legislation and regulatory expectations change.
Where previously the approach was mainly based on meeting benchmarks for maximum noise emissions, now it is about minimising the impact of any activity on the environment to the maximum extent possible. Therefore, our approach and thinking should evolve from traditional ways, promoting a culture of proactive and continuous improvement, implementation of best practice measures (and not only the bare minimums).