Project Overview: Noise Modelling for Factory Expansion, Scotland
Metrica Environmental Consulting was commissioned to support a major grain distillery expansion at an established industrial site in Scotland. The project required a robust noise impact assessment to demonstrate compliance with PPC environmental permit conditions and to provide assurance that the expanded operations would not adversely affect nearby noise-sensitive receptors.
As experienced acoustic consultants, our role was to undertake detailed noise modelling of the proposed plant and prepare a clear, auditable noise report suitable for regulatory submission.
The Challenge
The expansion introduced a large number of new noise‑emitting sources, including pumps, fans, cooling towers and plant located both internally and externally. The site operates continuously and is set within a wider industrial context, close to transport infrastructure and residential receptors.
The key challenge was to assess the cumulative effect of all new plant operating simultaneously under worst‑case conditions, ahead of the next four‑yearly systematic noise review required by the site’s PPC permit.
Our Approach
We carried out a comprehensive noise impact assessment in line with BS 4142 and SEPA guidance. Existing background noise data from previous permit assessments were reviewed and used to provide a representative baseline.
A detailed 3D noise modelling study was developed using SoundPLAN with ISO 9613‑2 propagation methodology. Over 160 individual noise sources were included, with plant locations and heights derived from client‑supplied models. Conservative assumptions were applied throughout, including all plant running at full capacity, open louvres and minimal screening.
Where equipment was housed within buildings, noise breakout was calculated using predicted sound insulation of the building envelope. This ensured the assessment remained robust even at an early design stage.
Outcome
The modelling demonstrated that predicted rating levels from the expanded distillery would remain below background noise levels during the day and would result in, at most, a minor exceedance at night. In all cases, impacts were assessed as low in the context of BS 4142.
The noise report also identified the plant contributing most to off‑site noise and set out proportionate mitigation options in line with Best Available Techniques. While no additional mitigation was required to achieve compliance, the assessment provides a clear framework should future noise management measures be needed.
Supporting Compliant Development
This project shows how early engagement with specialist noise consultants can support industrial expansion while protecting nearby communities. Our acoustic consultants delivered a clear, defensible assessment that enabled the client to progress the development with confidence and maintain ongoing permit compliance.
If you need support with noise modelling, a noise impact assessment or an environmental noise report, get in contact.
