Background
The Trust required planning approval for a single-storey modular kitchen facility within the car park south of Maidstone Hospital. As part of the retrospective consent (ref 23/502331/FULL), Condition 4 required submission of an odour extraction and treatment scheme compliant with EMAQ + Guidance on the Control of Odour and Noise from Commercial Kitchen Exhaust Systems (2018). Condition 5 required a noise impact assessment in accordance with BS 4142:2014+A1:2019.
Anderson Acoustics was commissioned to assess whether the cold-food preparation kitchen posed any odour and noise risk and to provide evidence to discharge the conditions.
What We Did
Site and Operation Review
- The proposed unit serves the hospital catering operation, providing preparation, storage, and dispatch areas but no cooking or heating equipment;
- Site reconnaissance and drawings confirmed the nearest residential receptors were ≈ 75 m south on Parsley Way, well separated from the hospital compound.
Odour Risk Assessment
Using the EMAQ + method, we evaluated dispersion, receptor distance, kitchen size, and cooking type:-
- Dispersion: No extraction canopy – 0 points
- Receptor distance: ≈ 75 m – 5 points
- Cooking activity: None – 0 points
- → Total = 5 → Low Risk
Because no hot-food preparation occurs, the EMAQ + criteria for extraction systems were not triggered. The assessment concluded the true odour risk was “Very Low”.
Hygiene and Maintenance Measures
We concluded the facility follows NHS food-hygiene cleaning protocols ensuring that normal sanitation alone prevents odour build-up. As such no additional filtration, extraction, or carbon systems were required, reducing cost and energy use.
Plant Noise Impact Assessment
- We assessed the impact of noise from installed plant (condensers and air conditioning units) on nearby residential receptors;
- We conducted six days of unattended background sound level measurements and attended source measurements of plant equipment. Our acoustic calculations considered propagation, screening, and intermittency;
- The rating level of plant noise at the worst-affected receptor was 20 dB, which is 15–18 dB below the background noise level (day/night) and as such no noise mitigation was required and criteria were met;
- Vibration control recommendations included anti-vibration mounts and resilient pipework connections;
- We confirmed that the plant noise levels comply with local authority criteria, satisfying planning requirements and ensuring minimal impact on residential amenity.
Why It Matters
Hospitals increasingly rely on modular catering units to meet service demand, yet these must comply with environmental planning controls. By clearly demonstrating that cold-food operations generate negligible odour, we enabled the Trust to gain approval without unnecessary mechanical systems. This project illustrates how targeted, evidence-based assessment can both protect amenity and deliver efficient, low-impact healthcare facilities.
Project Progress
Maidstone Borough Council approved the discharge of conditions 4 and 5 on 24th January 2024.
