Good air quality is important for our health and quality of life.
People in good health usually encounter no serious short term side effects from moderate levels of air pollution. However elevated levels and/or long term exposure to pollution can affect human health, ecosystems and buildings. People with lung or heart conditions are at greater risk, and asthmatics may find poor air quality triggers attacks or leads to increased use of inhalers.
On this page
- Air Quality
- Air Quality Management Area (AQMA)
- Air Quality in Saffron Walden January 2014
- Current Air Quality
- What Uttlesford is doing to promote improvements in Air Quality
- Regulation of Air Quality
Air quality in Uttlesford is determined by many factors, including traffic exhaust, emissions from local industry, and domestic sources.
The Environmental Health service monitors air quality under the framework for local air quality management set out in the Environment Act 1995, to assess whether national air quality objectives contained in the government's National Air Quality Strategy are being met. Air Quality standards are set for the following pollutants which are known to cause harm:
- Sulphur dioxide
- Nitrogen dioxide
- Particulate matter
- Carbon monoxide
Where national targets are not being, or are unlikely to be achieved, the local authority must declare an Air Quality Management Area (AQMA) and implement an Action Plan. Most AQMAs are declared as a result of nitrogen dioxide from road vehicle emissions.
Uttlesford declared an AQMA in May 2012 to include major road junctions in Saffron Walden, based on the annual mean for nitrogen dioxide not being met at the Debden Road/London Road junction and the Thaxted Road/East Street junction. The area is centred on Elm Grove off Hill Street and a map of the area is shown below:
The AQMA enables the Council to take air quality into account as a material consideration when determining planning applications or appeals for larger developments inside or close to the AQMA. An application must be accompanied by an Air Quality Assessment if one or both of the following apply:
- The development could lead to a measurable deterioration in air quality as a direct result
- The development would introduce or increase human exposure in areas where existing air quality does not meet the air quality standard
The assessment must consider:
- The existing air quality in the vicinity of the proposed development
- The likely impact on local air quality as a result of the proposed development including additional traffic and/or introduction of new emissions sources, such as combustion plant
- Proposed measures for mitigating the impact on air quality including design measures to limit public exposure
- The level of increased exposure by the public to pollutants taking account of any mitigation measures
If an application is approved, the Council can seek financial contributions towards mitigating the impacts.
Recent Press Coverage
A number of articles and letters have appeared in local newspapers recently concerning the effects of air pollution on health. These have suggested that development proposals for housing in the town have the potential to result in increases in vehicle emissions. Claims have been made that pollution levels are above legal limits and that there will be an increase in deaths of Saffron Walden residents.
The following information is based on actual air quality monitoring data as measured by Uttlesford District Council's Environmental Health service.
It concludes that generally air quality in Saffron Walden remains good with a low likelihood of any serious impacts on health. Mitigation measures will ensure that there is no deterioration of air quality. Better emission controls for vehicles from 2013 onwards are also expected to contribute to improved air quality in the town in the future.
Air Quality Standards
Air quality is measured against WHO and EU standards adopted into the UK Government's Air Quality Strategy (Defra, 2007) and legislation. These provide Air Quality Standards (AQSs)for key air pollutants and are set at levels below which no significant health effects would be expected in even in sensitive population groups.
The AQSs apply to places where members of the public are likely to be exposed to pollutants for significant periods of time.
Local authorities are required to work towards the AQSs which are prescribed in Regulations for that purpose.
Table 1 sets out the standards contained in the Regulations :
Air Quality Standard (AQS)
Nitrogen Dioxide (NO2)
200 μg/m3 not to be exceeded more than 18 times/yr
1 hour mean
50 μg/m3, not to be exceeded more than35 times a year
25μg/m3 to be met by 01/01/15
Information on current air quality including the five main pollutants that can cause material health effects is provided using an index produced by the Department for Environment Food & Rural Affairs (DEFRA) called the Daily Air Quality Index, which can be viewed on the Air Information Resource page of the DEFRA website.
Local Air Quality Monitoring Data
Air quality monitoring is undertaken at three automatic monitoring stations located in Saffron Walden, Takeley and Birchanger, and at 23 other sites throughout the district using diffusion tubes.
All combustion processes in air produce oxides of nitrogen, including Nitrogen dioxide (NO2) and nitric oxide (NO). Road transport is the main source, followed by the electricity supply industry and other industrial and commercial sectors.NO2 is associated with adverse effects on human health. At high levels NO2 causes inflammation of the airways, and long term exposure may affect lung function and respiratory symptoms. NO2 also enhances the response to allergens in sensitive individuals.
Nitrogen Dioxide Automatic Monitoring Data
Over the past 6 years the data for Uttlesford shows no exceedances of the annual mean Nitrogen Dioxide objective at the automatic monitoring sites, and in the years when the hourly mean was exceeded, the number recorded was within the number acceptable to meet the 1 hour standard.
The number of exceedances of the hourly mean were recorded as:
2008 = 2 ( Saffron Walden)
2009 = 0
2010 = 13* (Saffron Walden)
2011 = 1 (Stansted)
2012 = 0
2013 = 0
2014 = 0
*Defra have stated that 2010 was an unusually high year across the whole of the UK for NO2 nationally for climate reasons.
Diffusion tube monitoring data
Of the 26 monitoring sites in Uttlesford, no concentrations exceeded the objectives in 2014.
Central Saffron Walden continues to be designated as an Air Quality Management Area (AQMA).
It should also be noted that a number of the diffusion monitoring tubes, including those where the exceedances have occurred in the past, are located on street furniture for practical reasons, situated immediately alongside the carriageway. As a result they are exposed to higher levels of emissions than the neighbouring houses. .
The results from recent years are shown below.
Results of NO2 diffusion tubes 2007-2014
Annual Mean Concentrations (ug/m3)
Adjusted for Bias
(Bias Factor 0.89)
(Bias Factor 1.36)
(Bias Factor 0.92)
(Bias Factor 0.95)
(Bias Factor 0.80)
(Bias Factor 0.90)
(Bias Factor 0.97)
(Bias Factor 0.87)
Walden 1 PO High Street
Airport 1 Thatched Cottage
Walden 3 Gibson Gardens
Walden 4 YHA
Walden 5 Thaxted Road
Airport 2 Rose Cottage
Walden 11 33 High Street
Walden 12 Town Hall
Takeley Hill Hatfield Forest
Elman's Green Hatfield Forest
South Gate Hatfield Forest
Walden 16 London Road
Walden 17 Debden Road
Walden 18 Friends School
Walden Peaslands Rd
Walden Borough Lane
Stansted Chapel Hill
* Predicted Annual Mean at Receptor 39.60
$ Predicted Annual Mean at Receptor 39.3
a Concentrations annualised due to less than 75% data capture
Particulate Matter (PM) is categorised on the basis of the size of the particles.
PM10 consists of particles less than 10 micrometres in diameter, and PM2.5 consists of particles with a diameter of less than 2.5micrometres in diameter. Exposure to Particulate Matter (PM) is associated with respiratory and cardiovascular illness and mortality. The finer the particle, the greater the risk of inhalation deep into the respiratory system with associated ill health effects.
PM is made up of a wide range of materials and arise from a variety of sources. Concentrations of PM comprise primary particles emitted directly into the atmosphere from combustion sources and secondary particles formed by chemical reactions in the air. PM derives from both human-made and natural sources (such as sea spray and Saharan dust). In the UK the biggest human-made sources are stationary fuel combustion and transport. Road transport gives rise to primary particles from engine emissions, tyre and brake wear and other non-exhaust emissions. Other primary sources include quarrying, construction and non-road mobile sources.
There is currently continuous monitoring of PM undertaken by the Council at three locations, and Uttlesford District Council is one of the few local authorities in Essex currently monitoring for pm 2.5. The pm 2.5monitor was located in Saffron Walden in 2014. The results showed a mean concentration 19.6 μg/ m3 in 2014 compared to the AQS target of 25μg/m3 to be met by 01/01/15.
PM 10 continues to be monitored close to the M11 at Birchanger and in Takeley, and has previously been monitored in Saffron Walden. In 2014 there were no exceedances of the annual mean objective or the hourly mean. Exceedances of the 24-hour mean have occurred in previous years but the maximum number of times was in 2011 in Saffron Walden when 19 were recorded, well below the AQS maximum number permitted of 35 per year.
Generally air quality in Saffron Walden remains good with a low likelihood of any serious impacts on health. However the Council is not complacent and regards air quality as an important aspect affecting the quality of life within the town and district. It is keen to ensure that air quality does not deteriorate in the future nor that it should be adversely affected as a result of new developments.
The AQMA covering the town centre requires any proposal for development which may affect air quality within the AQMA to be supported by an Air Quality Impact Assessment and provide for mitigation measures where necessary, to ensure there is no worsening of the air quality.
In addition to junction improvements and other proposed mitigation measures, the introduction of revised EU wide emission controls for vehicles produced from 2013 onwards is expected to contribute to improved air quality within the town to reduce the likelihood of further exceedances of the AQSs
The Air Quality Strategy for England, Scotland, Wales and Northern Ireland (Volume 1) 2007
UDC Air Quality Progress Report June 2013
UDC Updating and Screening Assessment 2012
- Minimising emissions generated as a result of our own activities. This includes promotion of car sharing, home working, and use of clean fuel in the refuse vehicle fleet
- Considering air quality corporately and with other authorities to ensure a consistent and integrated approach is taken when formulating policies such as the Local Transport Plan
- Encouraging the public and businesses to reduce emissions
- Providing information to the public and businesses
- Enforcing legislative controls to reduce emissions
1. Industrial Emissions. The Pollution Prevention and Control Act 1999 requires that operators of certain industrial processes apply to either the Environment Agency or a local authority, depending on the nature of the process, for a permit to control air and other emissions. UDC permits 26 processes which are inspected at least annually to ensure compliance with the conditions of their permit. Processes permitted by local authorities are divided into two categories - those that have the potential to impact on air, land, water and the noise environment, called part A2 processes, of which there are two in Uttlesford. These permits also control other matters including waste management and energy efficiency. The remainder, called part B processes, are considered to impact only on the air, and include facilities such as larger petrol stations, users of solvents, concrete crushers and cement batching. Operators are required to comply with conditions which are deemed to meet best practical techniques available for controlling emissions. Failure to do so can result in legal action being taken.
A list of all sites holding a permit is available below:
Further information on the processes can be obtained by contacting the Environmental Health Section.
2. Statutory Nuisance. The Environmental Protection Act 1990 defines a number of Statutory Nuisances including bonfires, dust , fumes and gases emitted from premises. Where a local authority is satisfied that a statutory nuisance exists, is likely to exist or recur, it must serve a Notice on the person responsible to require abatement of the nuisance. Failure to comply with the terms of the Notice may result in prosecution. A leaflet explaining the controls for bonfires is available below:
3. Dark Smoke. The Clean Air Act 1993 regulates emissions of dark smoke from chimneys and from industrial or trade premises
4. Chimney Heights. The Clean Air Act 1993 requires local authorities to approve the height of chimneys from certain processes to ensure satisfactory dispersal of emissions into the atmosphere.
Further information about air quality in the county is available at www.essexair.org
Contact the Environmental Health department
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