Air Quality Dispersion Modelling

Air quality dispersion modelling estimates pollutant concentrations at homes, schools and other locations where exposure matters. Freshbreeze Environmental Ltd provides modelling support for planning applications and environmental permit projects across the UK. We review the sources, site evidence and authority requirements before agreeing the model, assessment scope and programme.

What is air quality modelling?

Air quality modelling uses specialist software to predict pollutant concentrations at specific locations, based on emission sources such as road traffic and industrial plant. It estimates how pollutants like nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5) will spread and where they’ll settle, then compares those levels against national air quality objectives. Modelling is used when a simple screening assessment isn’t enough to show whether a development is acceptable.

When do you need air quality modelling?

Modelling may be appropriate where screening cannot adequately establish the likely effects. Examples include:

• Developments that materially change road traffic emissions near existing homes or other sensitive locations.
• New occupied buildings close to busy roads or other pollution sources, where exposure needs further assessment.
• Boilers, CHP, generators or process emissions requiring investigation for planning or permitting.
• Projects where the local authority or regulator requests a detailed emissions assessment.

An AQMA location, a city centre address or a nearby school does not by itself determine whether modelling is necessary. See our air quality site screening criteria for the first questions to check.

If you’re unsure whether your project needs modelling, we can advise before you commit to a full assessment.

Our air quality modelling services

Dispersion modelling

Using models such as ADMS-Roads, we assess how emissions disperse in the surrounding environment and predict pollutant concentrations at nearby homes and other sensitive receptors. This is the core of most air quality assessments for planning.

Traffic emission modelling

We quantify how vehicle emissions affect local air quality, building emission inventories from traffic data and testing different scenarios. Where impacts are identified, we recommend mitigation to reduce traffic related pollution.

Related indoor air quality investigations

For concerns inside an occupied building, our indoor air quality service can investigate relevant pollutants and ventilation issues. We confirm the appropriate testing scope separately from an outdoor dispersion modelling assessment.

How our modelling process works

Step 1 — Initial consultation

We discuss your project, confirm what the planning authority requires, and agree the scope of modelling needed.

Step 2 — Data collection

We gather baseline air quality data, traffic inputs and details of emission sources, and identify the sensitive receptors around your site.

Step 3 — Technical modelling

We run the dispersion model to predict pollutant concentrations, test scenarios where relevant, and develop mitigation if the results call for it.

Step 4 — Reporting

You receive a clear report setting out our findings, how they compare against air quality objectives, and practical recommendations ready to submit with your application.

Why choose FreshBreeze for air quality modelling?

• Recognised methods — methods selected with reference to relevant IAQM and Defra guidance and the agreed assessment scope
• UK-wide coverage — serving London, Manchester, Birmingham and beyond
• Clear reporting — technical results explained in plain English, with practical next steps
• Responsive service — we work to your deadlines and coordinate with your transport consultant to avoid delays

Costs and timeframes

The fee and programme depend on the sources, study area, assessment scenarios and data available. We set out the modelling scope, information needed, exclusions and delivery programme in our written proposal before work begins.

Frequently asked questions

Do I need air quality modelling for my project?

It depends on the source, likely emissions, surrounding area and available evidence. We review these factors first. A location near a busy road or within an AQMA can justify further investigation, but does not automatically require detailed modelling.

How long does air quality modelling take?

We agree the programme once we have reviewed the sources, study area and available data. Please send your deadline with the enquiry. Obtaining traffic, plant or monitoring information can affect the delivery date.

What software do you use for air quality modelling?

We select the model to suit the sources and study area. For road traffic assessments, this can include ADMS-Roads. The report explains the model version, inputs and assumptions. The evidence and assessment scope determine its suitability for the project.

How much does air quality modelling cost?
Cost varies with the size and complexity of the scheme. Basic modelling is the most affordable option, while detailed assessments cost more. Contact us for a fixed quote for your project.

What information is needed for dispersion modelling?

• For traffic: road layout, annual average daily flows, vehicle composition, speeds and the assessment years.
• For plant: emission rates, stack position and height, discharge conditions and operating hours.
• For the site: plans, nearby buildings and sensitive locations, relevant baseline evidence and the required programme.

We identify suitable weather and background data and agree any additional information needed before the work begins.

How do you check the model results?

For road traffic studies, suitable local monitoring can support model verification. We explain the data used, any adjustment, limitations and uncertainty, and compare the relevant assessment scenarios. The method is tailored to the source and project.

What will the modelling report contain?

The agreed report sets out the sources, model inputs and assumptions, assessment locations, predicted concentrations, comparison with applicable assessment criteria and any mitigation recommendations. Tables or concentration maps are included where they help explain the findings.

Send your site details for a quote

Need reliable air quality modelling for a planning application or permit? Contact FreshBreeze Environmental for services across London, Manchester and Birmingham. Call 0121 827 2737 or email info@freshbreezeeltd.co.uk for a fixed quote.