Exceedances of air quality limit values due to traffic

Indicator Specification
Indicator codes: TERM 004
Created 18 Oct 2017 Published 07 Dec 2017 Last modified 26 Sep 2018
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This indicator compares concentrations of pollutants at background stations with those at traffic stations. This comparison provides an estimate of the increased levels of air pollution to which the population is exposed in areas with increased road traffic. It also provides a measure of the impact of the technical and non-technical measures adopted to reduce the road transport sector's contribution to observed pollutant concentrations.  The indicator makes use of official data submitted to the EEA’s Air Quality e-reporting database.

Assessment versions

Published (reviewed and quality assured)

Rationale

Justification for indicator selection

This indicator shows the effect transport has on air quality, focusing on particulate matter (both PM10 and PM2.5) and nitrogen dioxide (NO2). The negative impacts of these pollutants on human health are outlined in CSI004 (EEA, 2018a). Road transport is the largest (or among the largest) source of emissions for these selected pollutants. Especially in urban areas, where the majority of the European population lives and works, the contribution of road transport emissions to observed pollutant concentrations is especially high, leading to increased exposure to those pollutants. It is, therefore, relevant to compare concentrations observed at traffic stations (stations located close to road traffic emission sources, which are often in city centres) with those observed at background stations.

Scientific references

  • EEA, 2018a Exceedance of air quality limit values in urban areas, Core Set indicator 004 (CSI004), indicator AIR003, European Environment Agency
  • EU, 2008 Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 on ambient air quality and cleaner air for Europe.
  • WHO, 2000 Air Quality Guidelines for Europe. Second edition. WHO Regional Publications, European Series, No. 91. World Health Organization, Regional Office for Europe, Copenhagen, Denmark
  • WHO, 2006 WHO air qua lity guidelines for particulate matter, ozone, nitrogen dioxide and sulphur dioxide. Global update 2005. World Health Organization, Regional Office for Eu rope, Copenhagen, Denmark.
  • EEA, 2018b Emissions of air pollutants from transport, Indicator TERM 003, European Environment Agency
  • EEA, 2018c European Union emission inventory report 1990-2016 under the UNECE Convention on Long-range Transboundary Air Pollution (LRTAP), EEA Report No 6/2018, European Environment Agency.

Indicator definition

This indicator compares concentrations of pollutants at background stations with those at traffic stations. This comparison provides an estimate of the increased levels of air pollution to which the population is exposed in areas with increased road traffic. It also provides a measure of the impact of the technical and non-technical measures adopted to reduce the road transport sector's contribution to observed pollutant concentrations. 

The indicator makes use of official data submitted to the EEA’s Air Quality e-reporting database.

Units

The units used in this indicator are pollutant concentrations at traffic and background stations, measured in micrograms per cubic metre (µg/m3).

Policy context and targets

Context description

This indicator provides information relevant to current European air quality legislation related to the setting of national emission targets, the reduction of transport related emissions (discussed in detail in TERM003 (EEA, 2018b)) and the protection of human health from harmful air pollutant levels (EU, 2008). It is related to the WHO Air Quality Guidelines (WHO, 2000, 2006) for protecting public health.

Targets

EU ambient air quality limit values set by Directive 2008/50/EC for the protection of human health

  • A limit value for PM2.5 of 25 µg/m3 as an annual average. In force since 1 January 2015.
  • A limit value for PM10 of 50 µg/m3 as a daily average, not to be exceeded more than 35 times in a calendar year. In force since 1 January 2005.
  • An additional limit value for PM10 of 40 µg/m3 as an annual average. In force since 1 January 2005.
  • A limit value for NO2 of 200 µg/m3 as an hourly average, not to be exceeded more than 18 times in a calendar year. In force since 1 January 2010.
  • An additional limit value for NO2 of 40 µg/m3 as an annual average. In force since 1 January 2010.

WHO Air Quality Guidelines

  • Annual mean of PM2.5: 10 µg/m3
  • 24-hour mean of PM2.5 (99th percentile of the annual daily series (3 days per year)): 25 µg/m3
  • Annual mean of PM10: 20 µg/m3
  • 24-hour mean of PM10 (99th percentile of the annual daily series (3 days per year)): 50 µg/m3
  • Annual mean of NO2: 40 µg/m3
  • 1-hour mean of NO2: 200 µg/m3

Related policy documents

  • Directive (EU) 2016/2284, reduction of national emissions of certain atmospheric pollutants
    The directive is amending Directive 2003/35/EC (providing for public participation in respect of the drawing up of certain plans and programmes relating to the environment) and repealing Directive 2001/81/EC. It entered into force at the end of 2016 and aims at compliance with the 2012 amended Gothenburg Protocol. In July 2017, the EU ratified the 2012 amendments to the 1999 protocol.
  • Directive 2008/50/EC, air quality
    Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 on ambient air quality and cleaner air for Europe.

Key policy question

Is air pollution from the transport sector reducing?

Methodology

Methodology for indicator calculation

Data submitted to the Air Quality e-reporting database have been used. The selected stations include station types classified as 'traffic' for the traffic map and 'background' for the background map. Only stations for which at least 75 % of data per calendar year are valid are used. That is, in the case of daily values, those having more than 274 valid daily values per calendar year (or 275 days in a leap year). And in the case of hourly values, this means those stations with more than 6 570 valid hourly values per calendar year (or 6 588 hours in a leap year).

Average yearly data were obtained for PM2.5 and NO2. For PM10, the annual series of the daily values is ordered and the percentile 90.41 (P90.41) selected. P90.41 represents, in a complete series, the 36th highest value; if it is above 50 µg/m3, it suggests an exceedance of the PM10 daily limit value. Using the P90.41 diminishes the effect of the missing values. 

Methodology for gap filling

No gap-filling is applied to the air quality data in the EEA air quality databases.

Methodology references

No methodology references available.

Data specifications

EEA data references

Data sources in latest figures

Uncertainties

Methodology uncertainty

No uncertainty has been specified.

Data sets uncertainty

Air quality data are officially submitted by national authorities. It is assumed that data have been validated by the national data suppliers. The number of reported stations varies across countries.

Station characteristics and representativeness are often insufficiently documented. Locally (i.e. at the station level), the indicator is subject to year-on-year variations due to meteorological variability.

Rationale uncertainty

No uncertainty has been specified.

Further work

Short term work

Work specified here requires to be completed within 1 year from now.

Long term work

Work specified here will require more than 1 year (from now) to be completed.

General metadata

Responsibility and ownership

EEA Contact Info

Alberto Gonzalez Ortiz

Ownership

European Environment Agency (EEA)

Identification

Indicator code
TERM 004
Specification
Version id: 2
Primary theme: Transport Transport

Frequency of updates

Updates are scheduled once per year

Classification

DPSIR: State
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)

Related content

Data used

Latest figures and vizualizations

Relevant policy documents

Document Actions
European Environment Agency (EEA)
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1050 Copenhagen K
Denmark
Phone: +45 3336 7100