Air quality and new developments

Impact of new developments on air quality

All developments have a potential to impact on air quality, positively as well as negatively. Therefore it is important that the potential impact of new development on air quality is taken into account in planning decisions.

The National Planning Policy Framework (NPPF) requires that planning policies and decisions should: contribute towards compliance with limit values and objectives for air pollutants; take into account the cumulative impact from individual sites in local areas; identify opportunities to improve air quality and mitigate any impacts and be consistent with the Local Air Quality Action Plan. Applications for developments should give priority to more sustainable forms of travel and be designed to enable charging for plug-in and other ultra-low emission vehicles in safe, accessible and convenient locations.

Air quality impacts of developments will arise during both the construction/demolition and operational phases, and are particularly important to consider where:

  • the development is likely to generate a significant air quality impact in an area where air quality is known to be relatively poor e.g. within or adjacent to the Air Quality Management Area (AQMA)
  • the development is likely to expose people to existing sources of air pollution e.g. if the development is located in an area of poor air quality or the AQMA
  • the development itself could lead to an exceedance of an air quality objective and result in a requirement to designate an AQMA
  • granting planning permission is likely to adversely impact upon the implementation of air quality strategies and action plans.

Current Salford City Council planning policy EN17 - Pollution Control sets out the local approach to the relationship between planning and air quality.

Air quality assessment

An air quality assessment will consider the air pollution emission sources of all phases (e.g. demolition/construction/operation) of the development and the significance of any impacts. If necessary, it will propose mitigation measures to ensure that any impacts are minimised as far as is practicable and the development can proceed. The latest EPUK/IAQM guidance and DEFRA Local Air Quality Management Technical Guidance (TG16) should be used as current best practice guidance to assess and mitigate emissions, and also consider opportunities to improve air quality.

Planning applications will be assessed against a validation checklist to determine whether a supporting air quality assessment is required, which is in line with the EPUK/IAQM guidance.

Mitigation measures

Examples of mitigation measures that might be considered include the following:

  • Designing the internal layout so habitable rooms are removed from the pollutant source
  • Traffic reduction and / or management measures
  • Robust travel plans aimed at encouraging modal shift to low carbon sustainable travel modes
  • Financial incentives for walking, cycling and public transport
  • Incentivisation for low emission vehicles such as charging facilities or electric vehicle car clubs in apartments
  • Measures to control dust emissions from demolition, earthworks, construction and trackout activities

Preference should be given to measures that prevent emissions or avoid exposure/impacts to the pollutant by eliminating or isolating potential sources or by replacing sources or activities with alternatives.

For major developments, particularly those in areas where there is the cumulative impact from a number of developments or where a significant air quality impact is likely, a damage cost calculation may be required as part of the air quality assessment. Damage Costs are an estimation of the economic impact caused by the increased emissions of nitrogen dioxide (NO2) and particulates from the new development. Further information on calculating Damage Costs is available from DEFRA and the EPUK/IAQM guidance (PDF). The final damage costs can then be used to determine a proportionate contribution, or provision of, additional mitigation on site. Where on site mitigation is not possible off site measures may need to be considered. 

It is recommended that developers intending to submit plans that may have a significant impact on air quality (or any proposals for non-gas fuelled heating systems such as biomass or CHP) contact the local planning authority at the pre-application stage to discuss their proposals. Every effort should be made to obtain agreement with the planning authority on the appropriate datasets and methodologies to be used for air quality assessments.

This page was last updated on 9 April 2019

Rate this page