Air Quality Neutral Assessments (AQNA)
Assessments to demonstrate air quality neutrality in line with local requirements.
An AQNA is typically required where:
- A development is located within London or another authority with air quality neutrality policies
- The proposal exceeds defined size thresholds (e.g. residential units or commercial floor area)
- The local planning authority specifically requests it as part of the application process
What is an Air Quality Neutral Assessment?
An air quality neutral assessment is a study used to determine whether a proposed development will meet air quality neutrality requirements, meaning it will not introduce additional emissions beyond defined benchmark levels.
These assessments are most commonly required for developments in areas with specific planning policies, particularly in London, where air quality neutrality is set out in the Greater London Authority (GLA) guidance.
When is an Air Quality Neutral Assessment required?
It is often required alongside an air quality statement, air quality assessment or air quality impact assessment.
What does an Air Quality Neutral Assessment include?
The assessment evaluates emissions from two key sources:
- Building emissions (e.g. heating and energy use)
- Transport emissions (e.g. vehicle trips associated with the development)
Emissions are calculated and compared against benchmark values set by the GLA. These benchmarks define the maximum allowable emissions for a development to be considered “air quality neutral.”
What is the purpose?
The purpose of an air quality neutral assessment is to ensure that new developments:
- Do not worsen local air quality
- Meet policy-compliant emission limits
- Incorporate appropriate mitigation where required
If a development exceeds the benchmarks, mitigation measures such as energy efficiency improvements, low emission technologies, or transport strategies may be required to achieve compliance. Where these measures are not considered sufficient by the local planning authority, offset emissions may be calculated and a financial contribution determined.
