ANNEX IU.K.
Target values for arsenic, cadmium, nickel and benzo(a)pyrene
|
Pollutant | Target value |
---|
Arsenic | 6 ng/m3 |
Cadmium | 5 ng/m3 |
Nickel | 20 ng/m3 |
Benzo(a)pyrene | 1 ng/m3 |
ANNEX IIU.K.Determination of requirements for assessment of concentrations of arsenic, cadmium, nickel and benzo(a)pyrene in ambient air within a zone or agglomeration
I.Upper and lower assessment thresholdsU.K.
The following upper and lower assessment thresholds will apply:
| Arsenic | Cadmium | Nickel | B(a)P |
---|
Upper assessment threshold in percent of the target value | 60 %
(3,6 ng/m3)
| 60 %
(3 ng/m3)
| 70 %
(14 ng/m3)
| 60 %
(0,6 ng/m3)
|
Lower assessment threshold in percent of the target value | 40 %
(2,4 ng/m3)
| 40 %
(2 ng/m3)
| 50 %
(10 ng/m3)
| 40 %
(0,4 ng/m3)
|
II.Determination of exceedances of upper and lower assessment thresholdsU.K.
Exceedances of upper and lower assessment thresholds must be determined on the basis of concentrations during the previous five years where sufficient data are available. An assessment threshold will be deemed to have been exceeded if it has been exceeded during at least three calendar years out of those previous five years.U.K.
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 IIIU.K.Location and minimum number of sampling points for the measurement of concentrations in ambient air and deposition rates
I.Macroscale sitingU.K.
The sites of sampling points should be selected in such a way as to:U.K.
provide data on the areas within zones and agglomerations where the population is likely to be directly or indirectly exposed to the highest concentrations averaged over a calendar year;
provide data on levels in other areas within zones and agglomerations which are representative of the exposure of the general population;
provide data on deposition rates representing the indirect exposure of the population through the food chain.
Sampling points should in general be sited so as to avoid measuring very small micro-environments in their immediate vicinity. As a guideline, a sampling point should be representative of air quality in surrounding areas of no less than 200 m2 at traffic-orientated sites, at least 250 m × 250 m at industrial sites, where feasible, and several square kilometres at urban-background sites.
Where the objective is to assess background levels the sampling site should not be influenced by agglomerations or industrial sites in its vicinity, i.e. sites closer than a few kilometres.
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. In particular where Article 3(3) applies, the sampling points should be sited such that the application of BAT can be monitored.
Sampling points should also, where possible, be representative of similar locations not in their immediate vicinity. Where appropriate they should be co-located with sampling points for PM10.
II.Microscale sitingU.K.
The following guidelines should be met as far as practicable:U.K.
the flow around the inlet sampling probe should be unrestricted, without any obstructions affecting the airflow in the vicinity of the sampler (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 should be between 1,5 m (the breathing zone) and 4 m above the ground. Higher positions (up to 8 m) may be necessary in some circumstances. Higher siting may also be appropriate if the station is representative of a large area;
the inlet probe should not be positioned in the immediate vicinity of sources in order to avoid direct intake of emissions unmixed with ambient air;
the sampler’s exhaust outlet should be positioned so that recirculation of exhaust air to the sample inlet is avoided;
traffic-orientated sampling points should be at least 25 metres from the edge of major junctions and at least 4 m from the centre of the nearest traffic lane; inlets should be sited so as to be representative of air quality near the building line;
for the deposition measurements in rural background areas, the EMEP guidelines and criteria should be applied as far as practicable and where not provided for in the Annexes.
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.
III.Documentation and review of site selectionU.K.
The site selection procedures should be fully documented at the classification stage by such means as compass-point photographs of the surrounding area and a detailed map. Sites should be reviewed at regular intervals with repeated documentation to ensure that selection criteria remain valid over time.U.K.
IV.Criteria for determining numbers of sampling points for fixed measurement of concentrations of arsenic, cadmium, nickel and benzo(a)pyrene in ambient airU.K.
Minimum number of sampling points for fixed measurement to assess compliance with target values for the protection of human health in zones and agglomerations where fixed measurement is the sole source of information.U.K.
(a)Diffuse sourcesU.K.
|
Population of agglomeration or zone(thousands) | If maximum concentrations exceed the upper assessment threshold | If maximum concentrations are between the upper and lower assessment thresholds |
---|
As, Cd, Ni | B(a)P | As, Cd, Ni | B(a)P |
---|
0–749 | 1 | 1 | 1 | 1 |
750–1 999 | 2 | 2 | 1 | 1 |
2 000–3 749 | 2 | 3 | 1 | 1 |
3 750–4 749 | 3 | 4 | 2 | 2 |
4 750–5 999 | 4 | 5 | 2 | 2 |
≥ 6 000 | 5 | 5 | 2 | 2 |
(b)Point sourcesU.K.
For the assessment of pollution in the vicinity of point sources, the number of sampling points for fixed measurement should be determined taking into account emission densities, the likely distribution patterns of ambient air pollution and potential exposure of the population.
The sampling points should be sited such that the application of BAT as defined by Article 2(11) of Directive 96/61/EC can be monitored.
ANNEX IVU.K.Data quality objectives and requirements for air quality models
I.Data quality objectivesU.K.
The following data quality objectives are provided as a guide to quality assurance.
|
| Benzo(a)pyrene | Arsenic, cadmium and nickel | Polycyclic aromatic hydrocarbons other than benzo(a)pyrene, total gaseous mercury | Total deposition |
---|
— Uncertainty | | | | |
Fixed and indicative measurements | 50 % | 40 % | 50 % | 70 % |
Modelling | 60 % | 60 % | 60 % | 60 % |
— Minimum data capture | 90 % | 90 % | 90 % | 90 % |
— Minimum time coverage: | | | | |
Fixed measurements | 33 % | 50 % | | |
Indicative measurements | 14 % | 14 % | 14 % | 33 % |
The uncertainty (expressed at a 95 % confidence level) of the methods used for the assessment of ambient air concentrations 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 are given for individual measurements, which are averaged over typical sampling times, for a 95 % confidence interval. The uncertainty of the measurements should be interpreted as being applicable in the region of the appropriate target value. Fixed and indicative measurements must be evenly distributed over the year in order to avoid skewing of results.
The requirements for minimum data capture and time coverage do not include losses of data due to regular calibration or normal maintenance of the instrumentation. Twenty-four-hour sampling is required for the measurement of benzo(a)pyrene and other polycyclic aromatic hydrocarbons. With care, individual samples taken over a period of up to one month can be combined and analysed as a composite sample, provided the method ensures that the samples are stable for that period. The three congeners benzo(b)fluoranthene, benzo(j)fluoranthene, benzo(k)fluoranthene can be difficult to resolve analytically. In such cases they can be reported as sum. Twenty-four hour sampling is also advisable for the measurement of arsenic, cadmium and nickel concentrations. Sampling must be spread evenly over the weekdays and the year. For the measurement of deposition rates monthly, or weekly, samples throughout the year are recommended.
Member States may use wet only instead of bulk sampling if they can demonstrate that the difference between them is within 10 %. Deposition rates should generally be given as μg/m2 per day.
Member States may apply a minimum time coverage lower than indicated in the table, but not lower than 14 % for fixed measurements and 6 % for indicative measurements provided that they can demonstrate that the 95 % expanded uncertainty for the annual mean, calculated from the data quality objectives in the table according to ISO 11222:2002 — ‘Determination of the uncertainty of the time average of air quality measurements’ will be met.
II.Requirements for air quality modelsU.K.
Where an air quality model is used for assessment, references to descriptions of the model and information on the uncertainty shall be compiled. The uncertainty for modelling is defined as the maximum deviation of the measured and calculated concentration levels, over a full year, without taking into account the timing of the events.
III.Requirements for objective estimation techniquesU.K.
Where objective estimation techniques are used, the uncertainty shall not exceed 100 %.
IV.StandardisationU.K.
For substances to be analysed in the PM10 fraction, the sampling volume refers to ambient conditions.
ANNEX VU.K.Reference methods for assessment of concentrations in ambient air and deposition rates
I.Reference method for the sampling and analysis of arsenic, cadmium and nickel in ambient airU.K.
The reference method for the measurement of arsenic, cadmium and nickel concentrations in ambient air is currently being standardised by CEN and shall be based on manual PM10 sampling equivalent to EN 12341, followed by digestion of the samples and analysis by Atomic Absorption Spectrometry or ICP Mass Spectrometry. In the absence of a CEN standard method, Member States are allowed to use national standard methods or ISO standard methods.U.K.
A Member State may also use any other methods which it can demonstrate give results equivalent to the above method.
II.Reference method for the sampling and analysis of polycyclic aromatic hydrocarbons in ambient airU.K.
The reference method for the measurement of benzo(a)pyrene concentrations in ambient air is currently being standardised by CEN and shall be based on manual PM10 sampling equivalent to EN 12341. In the absence of a CEN standard method, for benzo(a)pyrene or the other polycyclic aromatic hydrocarbons referred to in Article 4(8), Member States are allowed to use national standard methods or ISO methods such as ISO standard 12884.U.K.
A Member State may also use any other methods which it can demonstrate give results equivalent to the above method.
III.Reference method for the sampling and analysis of mercury in ambient airU.K.
The reference method for the measurement of total gaseous mercury concentrations in ambient air shall be an automated method based on Atomic Absorption Spectrometry or Atomic Fluorescence Spectrometry. In the absence of a CEN standardised method, Member States are allowed to use national standard methods or ISO standard methods.U.K.
A Member State may also use any other methods which it can demonstrate give results equivalent to the above method.
IV.Reference method for the sampling and analysis of the deposition of arsenic, cadmium, mercury, nickel and polycyclic aromatic hydrocarbonsU.K.
The reference method for the sampling of deposited arsenic, cadmium, mercury, nickel and polycyclic aromatic hydrocarbons shall be based on the exposition of cylindrical deposit gauges with standardised dimensions. In the absence of a CEN standardised method, Member States are allowed to use national standard methods.U.K.
[V. Reference air quality modelling techniques U.K.
Reference air quality modelling techniques cannot be specified at present. The Commission may make amendments to adapt this point to scientific and technical progress. Those measures, designed to amend non-essential elements of this Directive, shall be adopted in accordance with the regulatory procedure with scrutiny referred to in Article 6(3).] U.K.