What's the air quality in Dacorum? NO₂ 10.6 µg/m³

In 2025 the average resident of Dacorum lived with background NO₂ of 10.6 µg/m³, Very High for England and Wales and 1.1 times the WHO guideline of 10. PM2.5 was 8.4 µg/m³, Very High for England and Wales and 1.7 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
8.4 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 Dacorum
Lower Higher

Is the air quality good in Dacorum?

Background NO₂ in Dacorum is 10.6 µg/m³, 1.1 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 Dacorum is 8.4 µg/m³, 1.7 times the WHO guideline of 5, and higher than the typical area (7.4). That puts it in the Very High 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): 10.6 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): 8.4 µg/m³

PM2.5 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 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 Dacorum has the cleanest air?

Little Gaddesden has the lowest background NO₂ of the 16 areas of Dacorum, at 7.8 µg/m³. Kings Langley has the highest, at 12.1 µg/m³. Average house prices are shown alongside, so you can weigh air quality against cost.

Areas of Dacorum by background NO₂, lowest first, with PM2.5 and average house price
AreaNO₂PM2.5Average price
Little GaddesdenHigh7.87.9£2,314,500
AldburyHigh7.97.9£672,750
WiggintonHigh8.17.9£698,725
Tring RuralHigh8.28.1£680,554
TringHigh8.38.0£558,321
Great GaddesdenHigh8.78.1£729,285
NorthchurchHigh8.88.0£561,000
Nettleden with Potten EndHigh8.98.1£877,400
BovingdonVery High9.38.4£627,441
BerkhamstedVery High9.48.1£800,034
FlaundenVery High9.58.4£977,500
MarkyateVery High9.98.3£407,900
ChipperfieldVery High10.28.5£873,863
FlamsteadVery High10.48.4£690,833
Nash MillsVery High11.68.7£456,361
Kings LangleyVery High12.18.8£641,041

Levels in µg/m³, 2025 annual average.

How does air quality in Dacorum compare with nearby areas?

Background NO₂ in Dacorum compared with the 6 nearest other areas in Hertfordshire.

Compare Dacorum 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 Dacorum, NO₂ can be much higher. Councils publish roadside monitoring in their annual air quality reports.

What else do people ask about Dacorum?

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

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 01:27 with the latest Land Registry data (September 2026). The Dacorum dataset covers 6,233 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.

About·Data methodology·Buying checklist·Privacy and cookies·YouTube