In recent years, UK planning authorities have taken a more robust approach to developments that pose a risk of odour pollution. Whether you’re building near a food business, operating a waste facility, or proposing a new kitchen extraction system, understanding and applying odour assessment guidance correctly is essential for avoiding objections and securing planning approval.
In this post, we outline what odour assessment guidance involves, how the IAQM guidelines inform planning decisions, and what developers must do to ensure compliance from day one.
What Is Odour Assessment Guidance?
Odour assessment guidance refers to the methods and criteria used by environmental consultants and local authorities to evaluate the potential impact of odour emissions on surrounding land uses. The most widely recognised standard in the UK is the IAQM (Institute of Air Quality Management) Odour Assessment for Planning document.
This guidance helps determine:
- Whether an odour-generating activity may cause a nuisance
- What level of assessment is required (qualitative or quantitative)
- How risk is calculated using a source–pathway–receptor model
- What mitigation, if any, is needed to reduce the odour impact
By following this framework, developers can demonstrate that their project won’t cause unacceptable loss of amenity for existing or future neighbours.
Why Is Odour Assessment Guidance Important for Planning?
Local authorities have a statutory responsibility to protect public amenity and environmental quality. This includes managing the risk of odour pollution from new or existing developments.
Odour assessment guidance is important because it:
- Helps planning officers evaluate environmental impact objectively
- Ensures compliance with the National Planning Policy Framework (NPPF)
- Protects sensitive receptors like homes, schools, and hospitals
- Reduces the risk of planning refusal or enforcement action
- Encourages better site design and appropriate odour mitigation measures
For developers, understanding and applying the right odour assessment guidance means fewer delays, smoother approvals, and greater confidence during the planning process.
When Is an Odour Assessment Required?
You may need to follow odour assessment guidance and submit a report if your project:
- Involves food production or commercial kitchens
- Includes waste transfer, treatment, or storage
- Is located near agricultural operations (e.g. poultry or pig farms)
- Introduces sensitive land uses (like housing) near odour sources
- Is flagged by the local Environmental Health Officer (EHO)
A typical requirement is to assess the odour risk using IAQM methodologies and propose mitigation where necessary.
Key Components of Odour Assessment Guidance
At Hawkins Environmental, we prepare odour assessments using a structured approach based on IAQM guidance, tailored to the scale and nature of the proposal.
A comprehensive odour assessment includes:
- Odour source characterisation: Type, frequency, and intensity of emissions
- Receptor identification: Proximity and sensitivity of homes, schools, or public spaces
- Pathway analysis: How odour may travel under various weather conditions
- Odour risk matrix: Assigning risk levels based on source strength and receptor distance
- Mitigation strategy: Detailing practical measures such as filters, stack heights, or enclosures
By applying odour assessment guidance correctly, you’re more likely to secure planning approval without costly objections or appeals.
Mitigating Odour Risks in Planning
If your odour assessment identifies a medium or high risk, mitigation will be necessary to bring the impact down to an acceptable level.
Common mitigation strategies include:
- Carbon filtration or scrubber systems
- Adequate stack heights to ensure odour dispersion
- Enclosed operations to contain emissions
- Operational controls, such as limiting hours or types of activity
- Maintenance and monitoring to ensure long-term effectiveness
Your odour consultant will recommend solutions aligned with local authority odour policy and Environmental Protection Act standards.
Why Choose Hawkins Environmental for Odour Reports?
At Hawkins Environmental, we provide planning-compliant odour impact assessments supported by the latest IAQM guidance. Our team works with developers, architects, and planning consultants to deliver:
- Clear, professional reports ready for submission
- Fast turnaround and practical advice
- Honest feedback on odour risks and mitigation options
- Expert support throughout the planning process
Whether you’re developing a new site or responding to EHO queries, we help you stay compliant and move forward with confidence.
Learn more: Air Quality & Odour Assessments
Call us: 01256 522332
Email: enquiry@hawkinsenvironmental.co.uk
FAQs
Q1: What is the IAQM odour guidance?
A1: It’s the UK’s best-practice standard for evaluating odour in planning. It provides a framework for assessing risk and advising on mitigation, widely accepted by local authorities.
Q2: Is odour assessment guidance legally binding?
A2: No, but it is considered a material planning consideration. Following recognised guidance like IAQM significantly increases your chances of approval and reduces risk of complaints.
Q3: What if my site is already near an odour source?
A3: You may still get planning approval if the odour exposure threshold is low or if suitable design and mitigation measures can be demonstrated. We assess this in detail within the report.