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

CHAPTER I GENERAL PROVISIONS

Article 1

Subject matter

This Directive lays down measures aimed at the following:

• 1. defining and establishing objectives for ambient air quality designed to avoid, prevent or reduce harmful effects on human health and the environment as a whole;

• 1. assessing the ambient air quality in Member States on the basis of common methods and criteria;

• 1. obtaining information on ambient air quality in order to help combat air pollution and nuisance and to monitor long-term trends and improvements resulting from national and Community measures;

• 1. ensuring that such information on ambient air quality is made available to the public;

• 1. maintaining air quality where it is good and improving it in other cases;

• 1. promoting increased cooperation between the Member States in reducing air pollution.

Article 2

Definitions

For the purposes of this Directive:

• 1. ‘ambient air’ shall mean outdoor air in the troposphere, excluding workplaces as defined by Directive 89/654/EEC ([^E0001]) where provisions concerning health and safety at work apply and to which members of the public do not have regular access;

• 1. ‘pollutant’ shall mean any substance present in ambient air and likely to have harmful effects on human health and/or the environment as a whole;

• 1. ‘level’ shall mean the concentration of a pollutant in ambient air or the deposition thereof on surfaces in a given time;

• 1. ‘assessment’ shall mean any method used to measure, calculate, predict or estimate levels;

• 1. ‘limit value’ shall mean a level fixed on the basis of scientific knowledge, with the aim of avoiding, preventing or reducing harmful effects on human health and/or the environment as a whole, to be attained within a given period and not to be exceeded once attained;

• 1. ‘critical level’ shall mean a level fixed on the basis of scientific knowledge, above which direct adverse effects may occur on some receptors, such as trees, other plants or natural ecosystems but not on humans;

• 1. ‘margin of tolerance’ shall mean the percentage of the limit value by which that value may be exceeded subject to the conditions laid down in this Directive;

• 1. ‘air quality plans’ shall mean plans that set out measures in order to attain the limit values or target values;

• 1. ‘target value’ shall mean a level fixed with the aim of avoiding, preventing or reducing harmful effects on human health and/or the environment as a whole, to be attained where possible over a given period;

• 1. ‘alert threshold’ shall mean a level beyond which there is a risk to human health from brief exposure for the population as a whole and at which immediate steps are to be taken by the Member States;

• 1. ‘information threshold’ shall mean a level beyond which there is a risk to human health from brief exposure for particularly sensitive sections of the population and for which immediate and appropriate information is necessary;

• 1. ‘upper assessment threshold’ shall mean a level below which a combination of fixed measurements and modelling techniques and/or indicative measurements may be used to assess ambient air quality;

• 1. ‘lower assessment threshold’ shall mean a level below which modelling or objective-estimation techniques alone may be used to assess ambient air quality;

• 1. ‘long-term objective’ shall mean a level to be attained in the long term, save where not achievable through proportionate measures, with the aim of providing effective protection of human health and the environment;

• 1. ‘contributions from natural sources’ shall mean emissions of pollutants not caused directly or indirectly by human activities, including natural events such as volcanic eruptions, seismic activities, geothermal activities, wild-land fires, high-wind events, sea sprays or the atmospheric re-suspension or transport of natural particles from dry regions;

• 1. ‘zone’ shall mean part of the territory of a Member State, as delimited by that Member State for the purposes of air quality assessment and management;

• 1. ‘agglomeration’ shall mean a zone that is a conurbation with a population in excess of 250 000 inhabitants or, where the population is 250 000 inhabitants or less, with a given population density per km² to be established by the Member States;

• 1. ‘PM10’ shall mean particulate matter which passes through a size-selective inlet as defined in the reference method for the sampling and measurement of PM10, EN 12341, with a 50 % efficiency cut-off at 10 μm aerodynamic diameter;

• 1. ‘PM2,5’ shall mean particulate matter which passes through a size-selective inlet as defined in the reference method for the sampling and measurement of PM2,5, EN 14907, with a 50 % efficiency cut-off at 2,5 μm aerodynamic diameter;

• 1. ‘average exposure indicator’ shall mean an average level determined on the basis of measurements at urban background locations throughout the territory of a Member State and which reflects population exposure. It is used to calculate the national exposure reduction target and the exposure concentration obligation;

• 1. ‘exposure concentration obligation’ shall mean a level fixed on the basis of the average exposure indicator with the aim of reducing harmful effects on human health, to be attained over a given period;

• 1. ‘national exposure reduction target’ shall mean a percentage reduction of the average exposure of the population of a Member State set for the reference year with the aim of reducing harmful effects on human health, to be attained where possible over a given period;

• 1. ‘urban background locations’ shall mean places in urban areas where levels are representative of the exposure of the general urban population;

• 1. ‘oxides of nitrogen’ shall mean the sum of the volume mixing ratio (ppbv) of nitrogen monoxide (nitric oxide) and nitrogen dioxide expressed in units of mass concentration of nitrogen dioxide (μg/m³);

• 1. ‘fixed measurements’ shall mean measurements taken at fixed sites, either continuously or by random sampling, to determine the levels in accordance with the relevant data quality objectives;

• 1. ‘indicative measurements’ shall mean measurements which meet data quality objectives that are less strict than those required for fixed measurements;

• 1. ‘volatile organic compounds’ (VOC) shall mean organic compounds from anthropogenic and biogenic sources, other than methane, that are capable of producing photochemical oxidants by reactions with nitrogen oxides in the presence of sunlight;

• 1. ‘ozone precursor substances’ means substances which contribute to the formation of ground-level ozone, some of which are listed in Annex X.

Article 3

Responsibilities

Member States shall designate at the appropriate levels the competent authorities and bodies responsible for the following:

• (a) assessment of ambient air quality;

• (b) approval of measurement systems (methods, equipment, networks and laboratories);

• (c) ensuring the accuracy of measurements;

• (d) analysis of assessment methods;

• (e) coordination on their territory if Community-wide quality assurance programmes are being organised by the Commission;

• (f) cooperation with the other Member States and the Commission.

Where relevant, the competent authorities and bodies shall comply with Section C of Annex I.

Article 4

Establishment of zones and agglomerations

Member States shall establish zones and agglomerations throughout their territory. Air quality assessment and air quality management shall be carried out in all zones and agglomerations.

CHAPTER II ASSESSMENT OF AMBIENT AIR QUALITY

SECTION 1 Assessment of ambient air quality in relation to sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter, lead, benzene and carbon monoxide

Article 5

Assessment regime

Each zone and agglomeration shall be classified in relation to those assessment thresholds.

However, classifications shall be reviewed more frequently in the event of significant changes in activities relevant to the ambient concentrations of sulphur dioxide, nitrogen dioxide or, where relevant, oxides of nitrogen, particulate matter (PM10, PM2,5), lead, benzene or carbon monoxide.

Article 6

Assessment criteria

• (a) one sampling point shall be installed every 100 000  km²;

• (b) each Member State shall set up at least one measuring station or may, by agreement with adjoining Member States, set up one or several common measuring stations, covering the relevant neighbouring zones, to achieve the necessary spatial resolution;

• (c) where appropriate, monitoring shall be coordinated with the monitoring strategy and measurement programme of the Cooperative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (EMEP);

• (d) Sections A and C of Annex I shall apply in relation to the data quality objectives for mass concentration measurements of particulate matter and Annex IV shall apply in its entirety.

Member States shall inform the Commission of the measurement methods used in the measurement of the chemical composition of fine particulate matter (PM2,5).

Article 7

Sampling points

• (a) the supplementary methods provide sufficient information for the assessment of air quality with regard to limit values or alert thresholds, as well as adequate information for the public;

• (b) the number of sampling points to be installed and the spatial resolution of other techniques are sufficient for the concentration of the relevant pollutant to be established in accordance with the data quality objectives specified in Section A of Annex I and enable assessment results to meet the criteria specified in Section B of Annex I.

The results of modelling and/or indicative measurement shall be taken into account for the assessment of air quality with respect to the limit values.

Article 8

Reference measurement methods

SECTION 2 Assessment of ambient air quality in relation to ozone

Article 9

Assessment criteria

Article 10

Sampling points

• (a) the supplementary methods provide sufficient information for the assessment of air quality with regard to target values, long-term objectives, information and alert thresholds;

• (b) the number of sampling points to be installed and the spatial resolution of other techniques are sufficient for the concentration of ozone to be established in accordance with the data quality objectives specified in Section A of Annex I and enable assessment results to meet the criteria specified in Section B of Annex I;

• (c) the number of sampling points in each zone or agglomeration amounts to at least one sampling point per two million inhabitants or one sampling point per 50 000  km², whichever produces the greater number of sampling points, but must not be less than one sampling point in each zone or agglomeration;

• (d) nitrogen dioxide is measured at all remaining sampling points except at rural background stations as referred to in Section A of Annex VIII.

The results of modelling and/or indicative measurement shall be taken into account for the assessment of air quality with respect to the target values.

Article 11

Reference measurement methods

CHAPTER III AMBIENT AIR QUALITY MANAGEMENT

Article 12

Requirements where levels are lower than the limit values

In zones and agglomerations where the levels of sulphur dioxide, nitrogen dioxide, PM10, PM2,5, lead, benzene and carbon monoxide in ambient air are below the respective limit values specified in Annexes XI and XIV, Member States shall maintain the levels of those pollutants below the limit values and shall endeavour to preserve the best ambient air quality, compatible with sustainable development.

Article 13

Limit values and alert thresholds for the protection of human health

In respect of nitrogen dioxide and benzene, the limit values specified in Annex XI may not be exceeded from the dates specified therein.

Compliance with these requirements shall be assessed in accordance with Annex III.

The margins of tolerance laid down in Annex XI shall apply in accordance with Article 22(3) and Article 23(1).

Article 14

Critical levels

Article 15

National PM2,5 exposure reduction target for the protection of human health

Article 16

PM2,5 target value and limit value for the protection of human health

Article 17

Requirements in zones and agglomerations where ozone concentrations exceed the target values and long-term objectives

Article 18

Requirements in zones and agglomerations where ozone concentrations meet the long-term objectives

In zones and agglomerations in which ozone levels meet the long-term objectives, Member States shall, in so far as factors including the transboundary nature of ozone pollution and meteorological conditions permit, maintain those levels below the long-term objectives and shall preserve through proportionate measures the best ambient air quality compatible with sustainable development and a high level of environmental and human health protection.

Article 19

Measures required in the event of information or alert thresholds being exceeded

Where the information threshold specified in Annex XII or any of the alert thresholds laid down therein is exceeded, Member States shall take the necessary steps to inform the public by means of radio, television, newspapers or the Internet.

Member States shall also forward to the Commission, on a provisional basis, information concerning the levels recorded and the duration of the periods during which the alert threshold or information threshold was exceeded.

Article 20

Contributions from natural sources

Article 21

Exceedances attributable to winter-sanding or -salting of roads

Article 22

Postponement of attainment deadlines and exemption from the obligation to apply certain limit values

Where the Commission has raised no objections within nine months of receipt of that notification, the relevant conditions for the application of paragraphs 1 or 2 shall be deemed to be satisfied.

If objections are raised, the Commission may require Member States to adjust or provide new air quality plans.

CHAPTER IV PLANS

Article 23

Air quality plans

In the event of exceedances of those limit values for which the attainment deadline is already expired, the air quality plans shall set out appropriate measures, so that the exceedance period can be kept as short as possible. The air quality plans may additionally include specific measures aiming at the protection of sensitive population groups, including children.

Those air quality plans shall incorporate at least the information listed in Section A of Annex XV and may include measures pursuant to Article 24. Those plans shall be communicated to the Commission without delay, but no later than two years after the end of the year the first exceedance was observed.

Where air quality plans must be prepared or implemented in respect of several pollutants, Member States shall, where appropriate, prepare and implement integrated air quality plans covering all pollutants concerned.

Article 24

Short-term action plans

However, where there is a risk that the alert threshold for ozone specified in Section B of Annex XII will be exceeded, Member States shall only draw up such short-term action plans when in their opinion there is a significant potential, taking into account national geographical, meteorological and economic conditions, to reduce the risk, duration or severity of such an exceedance. When drawing up such a short-term action plan Member States shall take account of Decision 2004/279/EC.

Article 25

Transboundary air pollution

CHAPTER V INFORMATION AND REPORTING

Article 26

Public information

• (a) ambient air quality in accordance with Annex XVI;

• (b) any postponement decisions pursuant to Article 22(1);

• (c) any exemptions pursuant to Article 22(2);

• (d) air quality plans as provided for in Article 22(1) and Article 23 and programmes referred to in Article 17(2).

The information shall be made available free of charge by means of any easily accessible media including the Internet or any other appropriate means of telecommunication, and shall take into account the provisions laid down in Directive 2007/2/EC.

Those reports shall summarise the levels exceeding limit values, target values, long-term objectives, information thresholds and alert thresholds, for the relevant averaging periods. That information shall be combined with a summary assessment of the effects of those exceedances. The reports may include, where appropriate, further information and assessments on forest protection as well as information on other pollutants for which monitoring provisions are specified in this Directive, such as, inter alia, selected non-regulated ozone precursor substances as listed in Section B of Annex X.

Article 27

Transmission of information and reporting

• (a) the changes made in that year to the list and delimitation of zones and agglomerations established under Article 4;

• (b) the list of zones and agglomerations in which the levels of one or more pollutants are higher than the limit values plus the margin of tolerance where applicable or higher than target values or critical levels; and for these zones and agglomerations:
• (i) levels assessed and, if relevant, the dates and periods when such levels were observed;
• (ii) if appropriate, an assessment on contributions from natural sources and from re-suspension of particulates following winter-sanding or -salting of roads to the levels assessed, as declared to the Commission under Articles 20 and 21.

Article 28

Implementing measures

However, the amendments may not have the effect of directly or indirectly modifying either of the following:

• (a) the limit values, exposure reduction targets, critical levels, target values, information or alert thresholds or long-term objectives specified in Annex VII and Annexes XI to XIV;

• (b) the dates for compliance with any of the parameters referred to in point (a).

The Commission shall also identify ways of streamlining the way data are reported and the reciprocal exchange of information and data from networks and individual stations measuring ambient air pollution within the Member States, in accordance with the regulatory procedure referred to in Article 29(2).

CHAPTER VI COMMITTEE, TRANSITIONAL AND FINAL PROVISIONS

Article 29

Committee

The period laid down in Article 5(6) of Decision 1999/468/EC shall be set at three months.

Article 30

Penalties

Member States shall lay down the rules on penalties applicable to infringements of the national provisions adopted pursuant to this Directive and shall take all measures necessary to ensure that they are implemented. The penalties provided for must be effective, proportionate and dissuasive.

Article 31

Repeal and transitional provisions

However, from 11 June 2008, the following shall apply:

• (a) in Directive 96/62/EC, paragraph 1 of Article 12 shall be replaced by the following: ‘1. The detailed arrangements for forwarding the information to be provided under Article 11 shall be adopted in accordance with the procedure referred to in paragraph 3.’;

• (b) in Directive 1999/30/EC, Article 7(7), footnote 1 in point I of Annex VIII and point VI of Annex IX shall be deleted;

• (c) in Directive 2000/69/EC, Article 5(7) and point III in Annex VII shall be deleted;

• (d) in Directive 2002/3/EC, Article 9(5) and point II of Annex VIII shall be deleted.

• (a) Article 5 of Directive 96/62/EC until 31 December 2010;

• (b) Article 11(1) of Directive 96/62/EC and Article 10(1), (2) and (3) of Directive 2002/3/EC until the end of the second calendar year following the entry into force of the implementing measures referred to in Article 28(2) of this Directive;

• (c) Article 9(3) and (4) of Directive 1999/30/EC until 31 December 2009.

However, the third, fourth and fifth indents of Article 7 of Decision 97/101/EC shall be deleted with effect from 11 June 2008.

Article 32

Review

As regards PM2,5, the review shall be undertaken with a view to establishing a legally binding national exposure reduction obligation in order to replace the national exposure reduction target and to review the exposure concentration obligation laid down in Article 15, taking into account, inter alia, the following elements:

• — latest scientific information from WHO and other relevant organisations,

• — air quality situations and reduction potentials in the Member States,

• — the revision of Directive 2001/81/EC,

• — progress made in implementing Community reduction measures for air pollutants,

Article 33

Transposition

When Member States adopt these measures, they shall contain a reference to this Directive or shall be accompanied by such reference on the occasion of their official publication. The methods of making such reference shall be laid down by Member States.

Article 34

Entry into force

This Directive shall enter into force on the day of its publication in the Official Journal of the European Union.

Article 35

Addressees

This Directive is addressed to the Member States.

ANNEX I

DATA QUALITY OBJECTIVES

A. Data quality objectives for ambient air quality assessment

	Sulphur dioxide, nitrogen dioxide and oxides of nitrogen and carbon monoxide	Benzene	Particulate matter (PM10/PM2,5) and lead	Ozone and related NO and NO2
Fixed measurements [^E0002]
Uncertainty	15 %	25 %	25 %	15 %
Minimum data capture	90 %	90 %	90 %	90 % during summer 75 % during winter
Minimum time coverage:
—  urban background and traffic	—	35 % [^E0003]	—	—
—  industrial sites	—	90 %	—	—
Indicative measurements
Uncertainty	25 %	30 %	50 %	30 %
Minimum data capture	90 %	90 %	90 %	90 %
Minimum time coverage	14 % [^E0005]	14 % [^E0004]	14 % [^E0005]	> 10 % during summer
Modelling uncertainty:
Hourly	50 %	—	—	50 %
Eight-hour averages	50 %	—	—	50 %
Daily averages	50 %	—	not yet defined	—
Annual averages	30 %	50 %	50 %	—
Objective estimation
Uncertainty	75 %	100 %	100 %	75 %

Member States may apply random measurements instead of continuous measurements for benzene, lead and particulate matter if they can demonstrate to the Commission that the uncertainty, including the uncertainty due to random sampling, meets the quality objective of 25 % and the time coverage is still larger than the minimum time coverage for indicative measurements. Random sampling must be evenly distributed over the year in order to avoid skewing of results. The uncertainty due to random sampling may be determined by the procedure laid down in ISO 11222 (2002) ‘Air Quality — Determination of the Uncertainty of the Time Average of Air Quality Measurements’. If random measurements are used to assess the requirements of the PM10 limit value, the 90,4 percentile (to be lower than or equal to 50 μg/m³) should be evaluated instead of the number of exceedances, which is highly influenced by data coverage.

Distributed over the year to be representative of various conditions for climate and traffic.

One day's measurement a week at random, evenly distributed over the year, or eight weeks evenly distributed over the year.

One measurement a week at random, evenly distributed over the year, or eight weeks evenly distributed over the year.

The uncertainty (expressed at a 95 % confidence level) of the assessment methods will be evaluated in accordance with the principles of the CEN Guide to the Expression of Uncertainty in Measurement (ENV 13005-1999), the methodology of ISO 5725:1994 and the guidance provided in the CEN report ‘Air Quality — Approach to Uncertainty Estimation for Ambient Air Reference Measurement Methods’ (CR 14377:2002E). The percentages for uncertainty in the above table are given for individual measurements averaged over the period considered by the limit value (or target value in the case of ozone), for a 95 % confidence interval. The uncertainty for the fixed measurements shall be interpreted as being applicable in the region of the appropriate limit value (or target value in the case of ozone).

The uncertainty for modelling is defined as the maximum deviation of the measured and calculated concentration levels for 90 % of individual monitoring points, over the period considered, by the limit value (or target value in the case of ozone), without taking into account the timing of the events. The uncertainty for modelling shall be interpreted as being applicable in the region of the appropriate limit value (or target value in the case of ozone). The fixed measurements that have to be selected for comparison with modelling results shall be representative of the scale covered by the model.

The uncertainty for objective estimation is defined as the maximum deviation of the measured and calculated concentration levels, over the period considered, by the limit value (or target value in the case of ozone), without taking into account the timing of the events.

The requirements for minimum data capture and time coverage do not include losses of data due to the regular calibration or the normal maintenance of the instrumentation.

B. Results of air quality assessment

The following information shall be compiled for zones or agglomerations within which sources other than measurement are employed to supplement information from measurement or as the sole means of air quality assessment:

• — a description of assessment activities carried out,

• — the specific methods used, with references to descriptions of the method,

• — the sources of data and information,

• — a description of results, including uncertainties and, in particular, the extent of any area or, if relevant, the length of road within the zone or agglomeration over which concentrations exceed any limit value, target value or long-term objective plus margin of tolerance, if applicable, and of any area within which concentrations exceed the upper assessment threshold or the lower assessment threshold,

• — the population potentially exposed to levels in excess of any limit value for protection of human health.

C. Quality assurance for ambient air quality assessment. Data validation

• 1.To ensure accuracy of measurements and compliance with the data quality objectives laid down in Section A, the appropriate competent authorities and bodies designated pursuant to Article 3 shall ensure the following:

• (i) that all measurements undertaken in relation to the assessment of ambient air quality pursuant to Articles 6 and 9 are traceable in accordance with the requirements set out in the harmonised standard for testing and calibration laboratories,

• (ii) that institutions operating networks and individual stations have an established quality assurance and quality control system which provides for regular maintenance to assure the continued accuracy of measuring devices. The quality system shall be reviewed as necessary and at least every five years by the relevant National Reference Laboratory

• (iii) that a quality assurance/quality control process is established for the process of data collection and reporting and that institutions appointed for this task actively participate, in the related Union-wide quality assurance programmes,

• (iv) that the National Reference Laboratories are appointed by the appropriate competent authority or body designated pursuant to Article 3 and are accredited for the reference methods referred to in Annex VI, at least for those pollutants for which concentrations are above the lower assessment threshold, according to the relevant harmonised standard for testing and calibration laboratories, the reference to which has been published in the Official Journal of the European Union pursuant to Article 2(9) of Regulation (EC) No 765/2008 setting out the requirements for accreditation and market surveillance. These laboratories shall also be responsible for the coordination in Member State's territory of the Union-wide quality assurance programmes to be organised by the Commission's Joint Research Centre and shall also be responsible for coordinating, on the national level, the appropriate use of reference methods, and the demonstration of equivalence of non-reference methods. National Reference Laboratories organising intercomparison on the national level should also be accredited according to the relevant harmonised standard for proficiency testing.

• (v) that the National Reference Laboratories, take part at least every three years in the Union-wide quality assurance programmes organized by the Commission's Joint Research Centre. If this participation produces unsatisfactory results then the national laboratory should demonstrate at the next participation in the intercomparison satisfactory remediation measures, and provide a report to the Joint Research Centre on these.

• (vi) that the national reference laboratories support the work done by the European network of National Reference Laboratories set up by the Commission.

• 2.All reported data under Article 27 shall be deemed to be valid except data flagged as provisional.

ANNEX II

Determination of requirements for assessment of concentrations of sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter (PM10 and PM2,5), lead, benzene and carbon monoxide in ambient air within a zone or agglomeration

A. Upper and lower assessment thresholds

The following upper and lower assessment thresholds will apply:

1. Sulphur dioxide

	Health protection	Vegetation protection
Upper assessment threshold	60 % of 24-hour limit value (75 μg/m3, not to be exceeded more than 3 times in any calendar year)	60 % of winter critical level (12 μg/m3)
Lower assessment threshold	40 % of 24-hour limit value (50 μg/m3, not to be exceeded more than three times in any calendar year)	40 % of winter critical level (8 μg/m3)

2. Nitrogen dioxide and oxides of nitrogen

	Hourly limit value for the protection of human health (NO2)	Annual limit value for the protection of human health (NO2)	Annual critical level for the protection of vegetation and natural ecosystems (NOx)
Upper assessment threshold	70 % of limit value (140 μg/m3, not to be exceeded more than 18 times in any calendar year)	80 % of limit value (32 μg/m3)	80 % of critical level (24 μg/m3)
Lower assessment threshold	50 % of limit value (100 μg/m3, not to be exceeded more than 18 times in any calendar year)	65 % of limit value (26 μg/m3)	65 % of critical level (19,5 μg/m3)

3. Particulate matter (PM10/PM2,5)

	24-hour average PM10	Annual average PM10	Annual average PM2,5 [^E0006]
Upper assessment threshold	70 % of limit value (35 μg/m3, not to be exceeded more than 35 times in any calendar year)	70 % of limit value (28 μg/m3)	70 % of limit value (17 μg/m3)
Lower assessment threshold	50 % of limit value (25 μg/m3, not to be exceeded more than 35 times in any calendar year)	50 % of limit value (20 μg/m3)	50 % of limit value (12 μg/m3)

The upper assessment threshold and the lower assessment threshold for PM2,5 do not apply to the measurements to assess compliance with the PM2,5 exposure reduction target for the protection of human health.

4. Lead

	Annual average
Upper assessment threshold	70 % of limit value (0,35 μg/m3)
Lower assessment threshold	50 % of limit value (0,25 μg/m3)

5. Benzene

	Annual average
Upper assessment threshold	70 % of limit value (3,5 μg/m3)
Lower assessment threshold	40 % of limit value (2 μg/m3)

6. Carbon monoxide

	Eight-hour average
Upper assessment threshold	70 % of limit value (7 mg/m3)
Lower assessment threshold	50 % of limit value (5 mg/m3)

B. Determination of exceedances of upper and lower assessment thresholds

Exceedances of upper and lower assessment thresholds shall be determined on the basis of concentrations during the previous five years where sufficient data are available. An assessment threshold shall be deemed to have been exceeded if it has been exceeded during at least three separate years out of those previous five years.

Where fewer than five years’ data are available, Member States may combine measurement campaigns of short duration during the period of the year and at locations likely to be typical of the highest pollution levels with results obtained from information from emission inventories and modelling to determine exceedances of the upper and lower assessment thresholds.

ANNEX III

Assessment of ambient air quality and location of sampling points for the measurement of sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter (PM10 and PM2,5), lead, benzene and carbon monoxide in ambient air

A. General

Ambient air quality shall be assessed in all zones and agglomerations in accordance with the following criteria:

• 1. Ambient air quality shall be assessed at all locations except those listed in paragraph 2, in accordance with the criteria established by Sections B and C for the location of sampling points for fixed measurement. The principles established by Sections B and C shall also apply in so far as they are relevant in identifying the specific locations in which concentration of the relevant pollutants are established where ambient air quality is assessed by indicative measurement or modelling.

• 1. Compliance with the limit values directed at the protection of human health shall not be assessed at the following locations:

• (a) any locations situated within areas where members of the public do not have access and there is no fixed habitation;

• (b) in accordance with Article 2(1), on factory premises or at industrial installations to which all relevant provisions concerning health and safety at work apply;

• (c) on the carriageway of roads; and on the central reservations of roads except where there is normally pedestrian access to the central reservation.

B. Macroscale siting of sampling points

• 1. Protection of human health

• (a) Sampling points directed at the protection of human health shall be sited in such a way as to provide data on the following:
• — the areas within zones and agglomerations where the highest concentrations occur to which the population is likely to be directly or indirectly exposed for a period which is significant in relation to the averaging period of the limit value(s),
• — levels in other areas within the zones and agglomerations which are representative of the exposure of the general population,

• (b) Sampling points shall in general be sited in such a way as to avoid measuring very small micro-environments in their immediate vicinity, which means that a sampling point must be sited in such a way that the air sampled is representative of air quality for a street segment no less than 100 m length at traffic-orientated sites and at least 250 m × 250 m at industrial sites, where feasible;

• (c) Urban background locations shall be located so that their pollution level is influenced by the integrated contribution from all sources upwind of the station. The pollution level should not be dominated by a single source unless such a situation is typical for a larger urban area. Those sampling points shall, as a general rule, be representative for several square kilometres;

• (d) Where the objective is to assess rural background levels, the sampling point shall not be influenced by agglomerations or industrial sites in its vicinity, i.e. sites closer than five kilometres;

• (e) Where contributions from industrial sources are to be assessed, at least one sampling point shall be installed downwind of the source in the nearest residential area. Where the background concentration is not known, an additional sampling point shall be situated within the main wind direction;

• (f) Sampling points shall, where possible, also be representative of similar locations not in their immediate vicinity;

• (g) Account shall be taken of the need to locate sampling points on islands where that is necessary for the protection of human health.

• 1. Protection of vegetation and natural ecosystems

Sampling points targeted at the protection of vegetation and natural ecosystems shall be sited more than 20 km away from agglomerations or more than 5 km away from other built-up areas, industrial installations or motorways or major roads with traffic counts of more than 50 000 vehicles per day, which means that a sampling point must be sited in such a way that the air sampled is representative of air quality in a surrounding area of at least 1 000  km². A Member State may provide for a sampling point to be sited at a lesser distance or to be representative of air quality in a less extended area, taking account of geographical conditions or of the opportunities to protect particularly vulnerable areas.

Account shall be taken of the need to assess air quality on islands.

C. Microscale siting of sampling points

In so far as is practicable, the following shall apply:

• — the flow around the inlet sampling probe shall be unrestricted (in general free in an arc of at least 270° or 180° for sampling points at the building line) without any obstructions affecting the airflow in the vicinity of the inlet (normally some metres away from buildings, balconies, trees and other obstacles and at least 0,5 m from the nearest building in the case of sampling points representing air quality at the building line),

• — in general, the inlet sampling point shall be between 1,5 m (the breathing zone) and 4 m above the ground. Higher siting may also be appropriate if the station is representative of a large area and any derogations should be fully documented,

• — the inlet probe shall not be positioned in the immediate vicinity of sources in order to avoid the direct intake of emissions unmixed with ambient air,

• — the sampler's exhaust outlet shall be positioned so that recirculation of exhaust air to the sampler inlet is avoided,

• — for all pollutants, traffic-orientated sampling probes shall be at least 25 m from the edge of major junctions and no more than 10 m from the kerbside. A ‘major junction’ to be considered here is a junction which interrupts the traffic flow and causes different emissions (stop&go) from the rest of the road.,

The following factors may also be taken into account:

• — interfering sources,

• — security,

• — access,

• — availability of electrical power and telephone communications,

• — visibility of the site in relation to its surroundings,

• — safety of the public and operators,

• — the desirability of co-locating sampling points for different pollutants,

• — planning requirements.,

Any deviation from the criteria listed in this Section shall be fully documented through the procedures described in Section D.

D. Documentation and review of site selection

The competent authorities responsible for air quality assessment shall for all zones and agglomerations fully document the site-selection procedures and record information to support the network design and choice of location for all monitoring sites. The documentation shall include compass-point photographs of the area surrounding monitoring sites and detailed maps. Where supplementary methods are used within a zone or agglomeration, the documentation shall include details of these methods and information on how the criteria listed in Article 7(3) are met. The documentation shall be updated as necessary and reviewed at least every 5 years, to ensure that selection criteria, network design and monitoring site locations remain valid and optimal over time. The documentation shall be provided to the Commission within 3 months of being requested.

ANNEX IV

MEASUREMENTS AT RURAL BACKGROUND LOCATIONS IRRESPECTIVE OF CONCENTRATION

A. Objectives

The main objectives of such measurements are to ensure that adequate information is made available on levels in the background. This information is essential to judge the enhanced levels in more polluted areas (such as urban background, industry related locations, traffic related locations), assess the possible contribution from long-range transport of air pollutants, support source apportionment analysis and for the understanding of specific pollutants such as particulate matter. It is also essential for the increased use of modelling also in urban areas.

B. Substances

Measurement of PM2,5 must include at least the total mass concentration and concentrations of appropriate compounds to characterise its chemical composition. At least the list of chemical species given below shall be included.

SO4 2–	Na+	NH4 +	Ca2+	elemental carbon (EC)
NO3 –	K+	Cl–	Mg2+	organic carbon (OC)

C. Siting

Measurements should be taken in particular in rural background areas in accordance with parts A, B and C of Annex III.

ANNEX V

Criteria for determining minimum numbers of sampling points for fixed measurement of concentrations of sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter (PM10, PM2,5), lead, benzene and carbon monoxide in ambient air

• A. Minimum number of sampling points for fixed measurement to assess compliance with limit values for the protection of human health and alert thresholds in zones and agglomerations where fixed measurement is the sole source of information

Population of agglomeration or zone (thousands)	If maximum concentrations exceed the upper assessment threshold [^E0007]	If maximum concentrations exceed the upper assessment threshold [^E0007]	If maximum concentrations are between the upper and lower assessment thresholds	If maximum concentrations are between the upper and lower assessment thresholds
Population of agglomeration or zone (thousands)	Pollutants except PM	PM [^E0008] (sum of PM10 and PM2,5)	Pollutants except PM	PM [^E0008] (sum of PM10 and PM2,5)
0-249	1	2	1	1
250-499	2	3	1	2
500-749	2	3	1	2
750-999	3	4	1	2
1 000 -1 499	4	6	2	3
1 500 -1 999	5	7	2	3
2 000 -2 749	6	8	3	4
2 750 -3 749	7	10	3	4
3 750 -4 749	8	11	3	6
4 750 -5 999	9	13	4	6
≥ 6 000	10	15	4	7

For nitrogen dioxide, particulate matter, benzene and carbon monoxide: to include at least one urban background monitoring station and one traffic-orientated station provided this does not increase the number of sampling points. For these pollutants, the total number of urban-background stations and the total number of traffic oriented stations in a Member State required under Section A(1) shall not differ by more than a factor of 2. Sampling points with exceedances of the limit value for PM10 within the last three years shall be maintained, unless a relocation is necessary owing to special circumstances, in particular spatial development.

Where PM2,5 and PM10 are measured in accordance with Article 8 at the same monitoring station, these shall count as two separate sampling points. The total number of PM2,5 and PM10 sampling points in a Member State required under Section A(1) shall not differ by more than a factor of 2, and the number of PM2,5 sampling points in the urban background of agglomerations and urban areas shall meet the requirements under Section B of Annex V.

For the assessment of pollution in the vicinity of point sources, the number of sampling points for fixed measurement shall be calculated taking into account emission densities, the likely distribution patterns of ambient-air pollution and the potential exposure of the population.

• B. Minimum number of sampling points for fixed measurement to assess compliance with the PM2,5 exposure reduction target for the protection of human health

One sampling point per million inhabitants summed over agglomerations and additional urban areas in excess of 100 000 inhabitants shall be operated for this purpose. Those sampling points may coincide with sampling points under Section A.

• C. Minimum number of sampling points for fixed measurements to assess compliance with critical levels for the protection of vegetation in zones other than agglomerations

If maximum concentrations exceed the upper assessment threshold	If maximum concentrations are between upper and lower assessment threshold
1 station every 20 000  km2	1 station every 40 000  km2

In island zones the number of sampling points for fixed measurement should be calculated taking into account the likely distribution patterns of ambient-air pollution and the potential exposure of vegetation.

ANNEX VI

Reference methods for assessment of concentrations of sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter (PM10 and PM2,5), lead, benzene, carbon monoxide, and ozone

A. Reference methods for the assessment of concentrations of sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter (PM10 and PM2,5), lead, benzene, carbon monoxide and ozone

1. Reference method for the measurement of sulphur dioxide

The reference method for the measurement of sulphur dioxide is that described in EN 14212:2012 ‘Ambient air — Standard method for the measurement of the concentration of sulphur dioxide by ultraviolet fluorescence’.

2. Reference method for the measurement of nitrogen dioxide and oxides of nitrogen

The reference method for the measurement of nitrogen dioxide and oxides of nitrogen is that described in EN 14211:2012 ‘Ambient air — Standard method for the measurement of the concentration of nitrogen dioxide and nitrogen monoxide by chemiluminescence’.

3. Reference method for the sampling and measurement of lead

The reference method for the sampling of lead is that described in Section A(4) of this Annex. The reference method for the measurement of lead is that described in EN 14902:2005 ‘Standard method for measurement of Pb/Cd/As/Ni in the PM10 fraction of suspended particulate matter’.

4. Reference method for the sampling and measurement of PM10

The reference method for the sampling and measurement of PM10 is that described in EN12341:2014 ‘Ambient Air — standard gravimetric measurement method for the determination of the PM10 or PM2,5 mass concentration of suspended particulate matter’.