What's the air quality in Knowsley? NO₂ 14.4 µg/m³

In 2025 the average resident of Knowsley lived with background NO₂ of 14.4 µg/m³, Very High for England and Wales and 1.4 times the WHO guideline of 10. PM2.5 was 7.4 µg/m³, Typical for England and Wales and 1.5 times the WHO guideline of 5. The typical area in England and Wales has NO₂ of 7.2 and PM2.5 of 7.4 µg/m³.

PM2.5
7.4 µg/m³
NO₂ for England and Wales
Very High
Figures for
2025 annual average

Modelled background levels averaged over where residents live (Census 2021), not roadside levels. Contains public sector information licensed under the Open Government Licence v3.0. Source: Defra modelled background pollution, 2025. How we calculate this

All house prices in Knowsley
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Is the air quality good in Knowsley?

Background NO₂ in Knowsley is 14.4 µg/m³, 1.4 times the WHO guideline of 10, and higher than the typical area (7.2). That puts it in the Very High band. Background PM2.5 in Knowsley is 7.4 µg/m³, 1.5 times the WHO guideline of 5, and lower than the typical area (7.4). That puts it in the Typical band. Most of England and Wales is above the WHO guideline for PM2.5, so the bands compare places with each other rather than giving a pass or fail.

Nitrogen dioxide (NO₂): 14.4 µg/m³

NO₂ level is Very High, on a scale from Very Low to Very High.

Very High means the highest fifth of areas in England and Wales for NO₂.

NO₂ bands for areas in England and Wales, in µg/m³, with the map colour for each
Very Lowup to 4.7
Low4.7 to 6.5
Typical6.5 to 7.7
High7.7 to 9.2
Very Highover 9.2

WHO guideline: 10 µg/m³ (in the Very High band). UK legal limit: 40 µg/m³.

Fine particles (PM2.5): 7.4 µg/m³

PM2.5 level is Typical, on a scale from Very Low to Very High.

Typical means the middle fifth of areas in England and Wales for PM2.5.

PM2.5 bands for areas in England and Wales, in µg/m³, with the map colour for each
Very Lowup to 6.0
Low6.0 to 7.2
Typical7.2 to 7.7
High7.7 to 8.2
Very Highover 8.2

WHO guideline: 5 µg/m³ (in the Very Low band). UK legal limit: 20 µg/m³, with a target of 10 µg/m³ in England by 2040.

The bands split every area we cover into fifths by its level, from Very Low to Very High. The map uses the same colours.

Which part of Knowsley has the cleanest air?

Cronton has the lowest background NO₂ of the 4 areas of Knowsley, at 13.1 µg/m³. Halewood has the highest, at 16.5 µg/m³. Average house prices are shown alongside, so you can weigh air quality against cost.

Areas of Knowsley by background NO₂, lowest first, with PM2.5 and average house price
AreaNO₂PM2.5Average price
CrontonVery High13.17.4£298,541
PrescotVery High13.57.4£196,667
WhistonVery High13.67.5£188,338
HalewoodVery High16.57.5£229,492

Levels in µg/m³, 2025 annual average.

How does air quality in Knowsley compare with nearby areas?

Background NO₂ in Knowsley compared with the 4 nearest other areas in Merseyside.

Compare Knowsley with a different area

Does this include busy roads?

No. These are background levels: yearly averages over 1 km squares, away from the immediate influence of roads. Right beside a busy road in Knowsley, NO₂ can be much higher. Councils publish roadside monitoring in their annual air quality reports.

What else do people ask about Knowsley?

More quick answers on house prices, sales, areas, green space, crime, air quality and listed buildings in Knowsley.

Where does this data come from?

Price information is from HM Land Registry, location boundaries are from OpenStreetMap, and households and population are from Nomis Census 2021 postcode estimates (21 March 2021). Parks and green space are from OS Open Greenspace. Contains OS data © Crown copyright and database right 2026. Crime is from police.uk street-level data. Contains public sector information licensed under the Open Government Licence v3.0. Source: police.uk. Listed buildings and scheduled monuments are from Historic England and Cadw, and conservation areas from planning.data.gov.uk. © Historic England 2026. Contains Ordnance Survey data © Crown copyright and database right 2026. Source: planning.data.gov.uk, Open Government Licence v3.0. Air quality is from Defra modelled background pollution maps. Contains public sector information licensed under the Open Government Licence v3.0. Source: Defra modelled background pollution, 2025.

Last updated 11 November 2026 at 01:40 with the latest Land Registry data (September 2026). The Knowsley dataset covers 4,762 postcodes.

Read our full data methodology

Contains HM Land Registry data © Crown copyright and database right 2026. This data is licensed under the Open Government Licence v3.0.

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