Air Quality Monitoring


Over the last few months, due to the lack of air quality monitoring being carried out in the area by CBC, and with growing concerns over traffic congestion and pollution in general, TRRA have been carrying out community wide air quality monitoring using nitrogen dioxide detecting diffusion tubes

Monitoring tube in place

The tubes were supplied via Friends of the Earth and were analysed by a certified laboratory at Gradko International who manufacture and analyse the majority of testing equipment used by organisations across the country.

Five monitoring locations were used based upon local knowledge of traffic hotspots and recent / proposed development with tubes being changed on a monthly basis.

The results from the last six months are as follows:

This table shows both the raw data and bias corrected data for each location where available. The results from the diffusion tubes require calibration and adjusting alongside government figures. This is called a bias adjustment. The results are adjusted for accuracy using a bias correction factor for the type of diffusion tube used. This is involves multiplying the results by 0.89.

A graphical representation of the bias adjusted figures shows a general trend of increasing levels at all five sites over the monitoring period:

Whilst no sites are currently likely to breach the established “danger” limit of 40µg/m3 (taken as an average over a year)  the recorded levels are higher than might be expected for a “semi-rural” suburb and are, in certain cases, higher than levels being recorded at acknowledged problem locations in the centre of Cheltenham.

The developments at Grovefield Way, new care home, Blenheim Villas, new offices next to Asda and the Park and Ride extension for the Cyber Park have not even started / opened yet.

It is a situation we can only see getting worse particularly when “destination” development is being allowed in the area and infrastructure is already unable to cope e.g. Arle Court roundabout will be at over 200% capacity based upon currently permissioned development.

Further background information about air quality and its effects are available in the FoE publication below:

Useful information to support your diffusion tube results


20 is plenty

Some residents have asked about implementation of a “20 is plenty” scheme in the area particularly with regards to addressing speeding issues on Reddings Road / The Reddings.

For information, Cheltenham Borough Council carried out a town wide consultation during the latter part of 2017, the results of which can be seen here:

Whilst there was a majority in favour, it appears any implementation would have to be agreed at a county level. There is also conflicting evidence as to the effectiveness of such measures actually reducing speeds and improving air quality, and no indication that it would necessarily encourage a modal shift in transport methods and a subsequent reduction in car use.

It should also be noted that even if such a scheme was introduced, the main roads through the area (including Reddings Road / The Reddings) would likely be exempt from any 20mph limit. See map below:


Any self enforcement measures such a speed humps and chicanes have previously been ruled out on roads such Reddings Road / The Reddings due to their designation as bus routes. The Section 106 money generated from the Asda development, which was originally intended for installing local traffic calming measures, has now all been spent on the A40 bus lane anyway.

The Reddings is due to be allocated a Vehicle Activated Sign which can be installed, and relocated to where residents feel there are specific problems, to improve speed awareness. Please email us with suggestions for suitable locations.

Family Active Travel Map: South West Cheltenham

At the link below is a map which has been produced by Sustrans, following various consultations with the community during the last year, that aims to highlight family friendly routes through the area for walking and cycling:

Cheltenham_Sustrans Active Together Map

Whilst we are aware that traffic congestion and air quality issues are being caused by vehicles travelling through, and to, the area, residents can play a part in reducing car usage as well as benefiting from increased levels of activity.

An ideal opportunity to try some of these routes is approaching in the shape of Cycle to Work Day on Wednesday 15th August 2018:

If you can think of any local businesses who might be interested in promoting this, or you have concerns about any particular routes or areas, please let us know.

For more information about Sustrans and the work that they do please visit: