A desktop odour impact assessment for a commercial kitchen in the UK is a structured, guidance-led evaluation designed to determine the likely significance of odour emissions arising from cooking activities without the need for on-site atmospheric dispersion modelling. Instead of complex modelling software, the assessment relies on the qualitative but technically robust IAQM (Institute of Air Quality Management) and EMAQ+ (Environmental Management and Assessment Quality) risk-based scoring system, which is widely used by local planning authorities when considering applications involving food-led premises. This method aligns with UK planning policy requirements under the National Planning Policy Framework (NPPF), the Clean Air Act, relevant local authority planning policies and various statutory nuisance principles defined under the Environmental Protection Act 1990. 

A desktop odour assessment using the IAQM/EMAQ+ scoring methodology provides planners, environmental health officers and developers with a consistent, transparent and evidence-based means of understanding how proposed kitchen operations may influence local amenity—particularly in sensitive, mixed-use urban environments where residential receptors often sit close to restaurants, cafés, takeaways and similar cooking establishments. The process begins with the collection and analysis of high-quality background information, which forms the foundation of the assessment. This typically includes the proposed menu type, anticipated cooking volumes, opening hours, the number and type of cooking appliances, the building layout, location of extraction points, surrounding land-use context, proximity to residents and businesses, and any constraints such as planning designations, conservation areas or dense urban morphology. Because it is a desktop study, all of this information is analysed remotely using publicly available data sources such as mapping systems, street-view imagery, architectural drawings, planning documents, environmental databases and the applicant’s own specifications. By ensuring that all relevant inputs are captured, the assessor can develop a clear understanding of the odour risk profile associated with the proposed kitchen and the environmental sensitivity of the setting.

Once the baseline context is established, the assessment turns to the IAQM/EMAQ+ odour risk rating methodology, which is designed specifically for commercial kitchens and is endorsed across the UK as a standard planning tool. Unlike dispersion modelling, which mathematically simulates odour travel and concentration, the IAQM scoring method evaluates three core elements: the level of odour generated, the effectiveness of any proposed odour control techniques, and the sensitivity of nearby receptors. These elements are assigned numerical scores and combined to determine an overall risk category, which then guides any required mitigation. The first stage of scoring considers the odour potential of the kitchen. Here, the assessment examines the cooking activities in detail—such as whether the operation involves frying, char-grilling, steaming, or oven-based cooking—and the likely frequency and intensity of these activities. A kitchen producing high-odour foods such as deep-fried products or grilled meats will be scored as having a higher odour potential than a café producing primarily low-odour foods. The portion of the IAQM matrix related to cooking processes is invaluable for differentiating between low-risk and high-risk commercial operations, and it ensures that the assessment reflects real-world conditions rather than generic assumptions.

The second major factor is receptor sensitivity, which plays a central role in UK odour planning assessments because the acceptability of odour emissions depends heavily on who may be affected. The IAQM/EMAQ+ methodology categorises receptors based on their sensitivity to odour annoyance, with homes, schools, healthcare facilities and outdoor amenity spaces being considered highly sensitive, while commercial and industrial receptors receive a lower sensitivity weight. During a desktop odour assessment, the assessor uses GIS mapping, satellite images, local planning records and street-level imagery to identify all receptors within a relevant radius of the extraction point, often ranging from 10 metres to over 100 metres depending on the context. The relationship between the exhaust termination height and receptor elevation is also reviewed, since extracting at roof height typically reduces the potential for immediate downdrafts or direct plume impacts. The presence of narrow urban canyons, enclosed courtyards or low-level vents may increase sensitivity even where distances appear acceptable, so the qualitative nature of the IAQM scoring system allows the assessor to take account of micro-environmental factors that might otherwise be overlooked in a purely numerical model.

The third scoring element is the proposed odour control system, which is central to determining whether the residual odour risk is acceptable for planning purposes. IAQM and EMAQ+ provide a detailed, tiered classification of filtration and treatment options ranging from simple grease filters to more advanced systems such as electrostatic precipitators (ESPs), activated carbon filtration, ultraviolet ozone treatment (UV-O), hybrid systems or bespoke engineered solutions. In a desktop odour assessment, the assessor reviews the design of the extraction system—including duct length, flow rates, velocity, filter stages and termination height—to determine whether the odour mitigation measures are proportionate to the odour risk and receptor sensitivity. If only basic filtration is proposed for a high-odour kitchen located close to residential windows, the scoring matrix will reflect an increased likelihood of unacceptable odour impacts. Conversely, if an operator proposes a multi-stage filtration system with appropriate maintenance regimes, the residual risk score will be substantially lower. This helps planners and applicants understand exactly what level of investment and design refinement is required to achieve compliance.

Once the assessor has scored the odour potential, receptor sensitivity and mitigation effectiveness, the IAQM/EMAQ+ matrix is used to calculate the overall odour risk rating, which usually falls into categories such as low, medium, high or very high risk. This risk rating forms the core output of the desktop odour assessment and directly influences planning recommendations. A low risk rating typically means the proposed kitchen is unlikely to cause odour nuisance and the development can usually proceed with the proposed extraction system. A medium risk rating may require additional mitigation or slight adjustments to the filtration design. A high or very high risk category signals that the kitchen, in its proposed form, may cause unacceptable odour impacts unless significant enhancements to the odour control system are implemented. Importantly, this risk-based approach is consistent with UK planning principles that require developments to avoid significant adverse impacts on health and amenity, while still supporting economic growth and the operation of businesses.

A desktop odour impact assessment also considers legal and policy frameworks alongside IAQM scoring. Under the Environmental Protection Act 1990, odour from commercial kitchens can be treated as a statutory nuisance if it unreasonably interferes with nearby properties. Although planning consent does not override statutory nuisance law, a robust assessment helps developers demonstrate that they have taken reasonable steps to minimise odour emissions. The Clean Air Act may apply if the kitchen proposes combustion appliances or if flue height adjustments are necessary. Local planning policy—such as London’s Air Quality Neutral requirements or local environmental protection policies in other regions—also play an important role. The assessor reviews all of these elements to ensure the proposal aligns with national and local expectations for maintaining good air quality and protecting residential amenity.

An essential element of the desktop process is that it builds a clear, auditable justification for each score assigned within the IAQM/EMAQ+ matrix. Because the assessor relies on documented evidence, photographs, mapping tools and technical specifications rather than on-site measurements, the desktop assessment must thoroughly explain how each data source informs the scoring outcome. This ensures transparency and gives planning officers confidence in the conclusions, particularly where decisions may be challenged. The assessment may also provide recommendations on maintenance schedules, cleaning frequencies for filters, replacement timelines for carbon media, and considerations for future growth of the kitchen operations. These practical recommendations are crucial because even well-designed systems can fail to perform adequately if proper maintenance is not carried out.

Overall, a desktop odour impact assessment based on the IAQM/EMAQ+ scoring framework is a valuable planning tool that combines scientific principles, regulatory requirements and professional judgement to produce a reliable evaluation of odour risk for commercial kitchens in the UK. It provides a cost-effective and proportionate method for assessing odour impacts, especially for small to medium-sized developments where full dispersion modelling would be excessive. By following the structured methodology set out in recognised professional guidance, the assessment supports planning compliance, protects local amenity and ensures that cooking establishments operate responsibly within increasingly dense urban environments. The result is a balanced approach that enables culinary businesses to thrive while giving local authorities the confidence that odour emissions will be effectively controlled.