Background
Following multiple complaints from residents on Providence Place, Brighton & Hove City Council (BHCC) served a Noise Abatement Notice (Ref: 2017/ 00205/ EPA80C/EH) against the KFC restaurant on London Road.
Concerns centred on persistent noise from rooftop extract fans and cooking odour emissions during late-night operations. Despite previous remedial works, the Environmental Health Officer confirmed that statutory nuisance on noise grounds remained unresolved.
Anderson Acoustics was commissioned by Caskade Caterers Ltd to undertake a combined noise and odour investigation, assess compliance against BS 4142:2014 and DEFRA/EMAQ+ guidance, and design mitigation to abate the nuisance.
What we did
Site Investigation and Acoustic Survey
- Attended daytime and night-time measurements were carried out at Providence Place, representing the nearest noise-sensitive residential façades.
- Noise from the rooftop extraction plant was found to be the dominant night-time source, with measured levels of 61 dB LAeq during operation and 53 dB LA90 background noise.
- Using BS 4142 methodology, the plant’s rating level was 7 dB above background, indicating an adverse impact and confirming BHCC’s findings.
Plant Assessment and Mitigation Design
The rooftop plant comprised paired axial extract and intake fans within constrained ductwork. The system suffered from airflow resistance, forcing the fans to operate at higher duty and noise output. We proposed a complete replacement of the fan and attenuator assemblies, including:
- High-performance in-duct attenuators (to achieve 12 dB attenuation);
- Clad ductwork with service hatches to reduce breakout noise;
- Louvred inlets and outlets for acoustic efficiency;
- Maintenance regimes to prevent grease build-up affecting attenuator performance.
Post-mitigation calculations predicted a rating level 1 dB below background, satisfying BHCC’s enforcement requirement.
Odour Source and Control Assessment
The kitchen operation (frying of chicken) was classified as high odour risk. Baseline inspections detected faint but noticeable odour near Providence Place under calm conditions, though negligible during windy periods.
Mitigation options were reviewed under DEFRA’s Guidance on the Control of Odour and Noise from Commercial Kitchen Exhaust Systems:
- Fine filtration and carbon systems were rejected due to increased airflow resistance and potential noise rise;
- Ozone injection system was recommended to oxidise odorous compounds without affecting fan performance;
- Regular canopy and duct cleaning maintained every three months.
Outcome
Our assessment and recommendations provided a clear pathway for KFC Brighton to resolve noise and odour complaints, ensuring compliance with statutory requirements and improving relations with the local community. There was no further enforcement action by BHCC following our assessment.
Why It Matters
This investigation illustrates the importance of integrated noise and odour control in urban food operations. By combining detailed acoustic measurement with practical engineering design, we provided the client with a cost-effective route to compliance while maintaining operational airflow and efficiency. It demonstrates how robust technical evidence can turn enforcement into improvement – protecting community amenity and enabling business continuity.
