Air Quality Assessments and the Planning Process

Air Quality Assessments and the Planning Process

Air quality and odour assessments are often required by planning applications to ensure that the proposed development does not have an adverse impact on local air quality or create unacceptable levels of odour for nearby residents.

In the UK, there are several types of planning applications, including:

  1. Full Planning Application
  2. Outline Planning Application
  3. Reserved Matters Application
  4. Change of Use Application

Each type of application has specific criteria, documentation and validation requirements that must be met to be approved. Furthermore, different amounts of information pertaining to air quality and odour are required, depending on the type of application and local environmental conditions.

This post describes what information is normally required for air quality for different applications. It is, however, essential to carefully check the validation checklist provided by the local planning authority, read their pre-application advice and speak to specialists such as Greenavon to increase the chance of a successful outcome. Planning consultant and some architects can also assist in ensuring that the necessary information is included in applications.

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Outline Planning Permission and Air Quality

An outline planning application in the UK is a preliminary stage of the planning process, where the applicant seeks approval for the principle of a proposed development (e.g. location, size and scale), rather than its detailed design.

For outline planning applications, it is essential that you can identify the developable footprint of the proposal. For air quality, this means ascertaining the area of the site that is below the UK Air Quality Standards, identifying hotspots, and ensuring that the quantum of development is not so large as to cause significant impacts elsewhere in the vicinity. For odour, an odour assessment might be required to identify how close to a sewage treatment works, or another odorous source, you can build.

Without answering these questions at Outline stage, it is impossible for the local authority to grant the principal of development acceptable. For small sites set in areas of good air quality or away from odorous sources, screening assessments or brief conversations with the local authority air quality officer can often negate the need for detailed assessments of odour and air quality.

At Outline stage, there are no details on how the development will be constructed and as such, the assessment of the air quality effects associated with construction are of little value. As an appropriate level of air quality and dust mitigation can almost always be recommended at a later planning stage, construction does not always need to be considered for Outline applications.

Reserved Matters Applications and Air Quality

A Reserved Matters application is a type of planning application that is made after outline planning permission has been granted for a development and seeks approval for the specific details of the development, such as the design and layout of buildings, access arrangements, landscaping, and other matters that have been reserved for future consideration. These details are often requested via planning conditions.

Common planning conditions relating to air quality include the provision of dust management plans and air quality mitigation statements, which set out how the development will minimise emissions and promote sustainability. In some cases air quality assessments are also required where the principle of the development was not fully assessed at outline stage, or where the design was not sufficiently progressed to assess (e.g. if the energy strategy had not been chosen).

It is at Reserved Matters stage that detailed information relating to the energy, transport and construction materials and methods becomes available. This information can then be used to undertake a detailed air quality assessment, with recommendations being incorporated into the final design. Across the UK, there are several different air quality assessment requirements, depending on location and conditions will be placed on proposals to ensure they meet these specific local requirements. In London, conditions relating to air quality neutral assessments and air quality positive assessments are often required.

Full Applications and Air Quality

A full planning application in the UK is a detailed application that seeks approval for the specific design and layout of a proposed development, without undertaking a preliminary Outline application.

These types of application are detailed enough so that comprehensive air quality and odour assessments can be undertaken to accompany the application. Developers risk refusal if air quality and odour assessments have not been undertaken at this stage, as the local authority need to ensure that the proposal will not significantly impact, or be significantly impacted, by poor air quality or adverse odours during construction and operation.

Change of Use Application: Air Quality & Odour

A change of use application is a type of planning application that is made when a person or organization intends to change the use of a building or piece of land from one use class to another. The use classes are defined in the UK’s Town and Country Planning (Use Classes) Order 1987 and determine the type of uses that are allowed in a particular area without the need for planning permission.

There has been a dramatic rise in the demand for food deliveries since the Covid-19 pandemic, which has resulted in a large increase in the change of use applications from retail, or other use, to hot food takeaway or restaurants. These applications tend to occur in busy urban environments and as a result, there are many ‘noses’ which could be adversely impacted by odours released from the proposed takeaway. As such, odour assessments are required to ensure that change of use applications proposing restaurants and takeaways include sufficient odour mitigation in the form of abatement technology and odour management plans.

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There is also a trend in urban intensification, which is proposing the change of use of retail spaces and storage facilities into residential use. In terms of air quality, residential use is considered far more sensitive to pollution than a retail space, as you would expect a member of the public to spend far longer periods at home, than at a shop. As such, the allowable pollution levels for residential spaces are far lower than retail spaces. Retail spaces are often located in busy urban environments, adjacent to major roads. Air quality assessments are, therefore, required to predict pollution levels at the address and recommend appropriate ventilation strategies.

How can Greenavon support?

Air quality and odour assessments are required to avoid unforeseen environmental impacts which might affect the users of the proposal, or nearby residents. The results of the air quality and odour assessments will form part of the supporting information submitted and will be used by the local planning authority to make a decision on whether to grant planning permission.

The different types of application often include varying information pertaining to air quality and odour. For reserved matters, full planning and change of use applications, there should be sufficient detail to allow a comprehensive assessment of air quality and odour. However, the details of a proposal are usually not sufficiently progressed at outline stage to allow a comprehensive air quality and odour assessments. However, it is essential that an outline application can demonstrate that the quantum of your development is acceptable, and in keeping with the local area, to avoid risk of refusal.

It is strongly recommended that you speak to environmental specialists, including air quality and acoustic consultants at the earliest stage of design, for all proposals. By doing this, you can incorporate positive design choices, avoid expensive redesigns and minimise the risk of delays and refusal. For a free consultation, please feel free to contact Greenavon.

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