ENVIRONMENT & AIR QUALITY METHODOLOGY

Air Quality, Flood Risk & Green Space

We measure environmental quality using DEFRA Daily Air Quality Index (DAQI) models, Environment Agency statutory flood risk zones, and green space proximity analysis.

Safety Schools Broadband Environment Transport Housing

Data Provenance & Specs

PublisherDEFRA & EA

Update CadenceDaily / Quarterly

Spatial Unit1km Grid & Zones

LicenceOGL v3.0

DEFRA Air Quality Index (DAQI)

DAQI Band	Index Value	Health Descriptor
Low Air Pollution	Index 1 – 3	Air quality is good; minimal health risk for general population.
Moderate Air Pollution	Index 4 – 6	Sensitive individuals may experience mild respiratory symptoms.
High Air Pollution	Index 7 – 9	Anyone experiencing discomfort should reduce strenuous activity.
Very High Air Pollution	Index 10	General population should reduce physical exertion outdoors.

Important Technical Limitations

Grid Modeling: Air quality data represents 1km² background grid averages, not hyper-local micro-climate readings on individual street corners.
Flood Risk Bands: Reflect Environment Agency statutory flood risk zones (Zone 1, 2, 3), not individual property structural defenses.

Data Attribution

Contains public sector information licensed under the Open Government Licence v3.0, sourced from DEFRA & Environment Agency.