The Air Quality Standards (Wales) Regulations 2007

The uncertainty for modelling and objective estimation is defined as the maximum deviation of the measured and calculated concentration levels, over the period considered by the limit value, without taking into account the timing of the events.

9

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.

10

The National Assembly may allow for random measurements to be made instead of continuous measurements for benzene if the uncertainty, including the uncertainty due to random sampling, meets the quality objective of 25%. Random sampling must be spread evenly over the year.

PART 2 — Group B pollutants, polycyclic aromatic hydrocarbons and total gaseous mercury

11

The data quality objectives set out in the table and paragraphs below are provided to guide quality assurance programmes—

12

The uncertainty (expressed at a 95 % confidence level) of the methods used for the assessment of ambient air concentrations must be evaluated in accordance with the CEN Guide to the Expression of Uncertainty in Measurement (ENV 13005-1999)[^f00013], 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, 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.

13

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 may 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 where they are difficult to resolve analytically. In such cases they can be reported as sum. Twenty-four hour sampling is also recommended as 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.

14

The National Assembly may allow for use of wet only instead of bulk sampling if it can be demonstrated to its satisfaction that the difference between them is within 10 %. Deposition rates should generally be given as μg/m² per day.

15

The National Assembly 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 it is satisfied that it can be demonstrated 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.

PART 3 — Ozone and nitrogen dioxide assessed at ozone sampling points

16

The data quality objectives set out in the table and paragraphs below, for allowed uncertainty of assessment methods, and of minimum time coverage and of data capture of measurement, are provided to guide quality-assurance programmes—

17

The uncertainty (on a 95% confidence interval) of the measurement methods must be evaluated in accordance with the principles laid down in the “Guide to the Expression of Uncertainty of Measurements” (ISO 1993) or the methodology in ISO 5725-1 “Accuracy (trueness and precision) of measurement methods and results” (ISO 1994) or equivalent. The percentages for uncertainty in the table are given for individual measurements, averaged over the period for calculating target values and long-term objectives, for a 95% confidence interval. The uncertainty for continuous fixed measurements should be interpreted as being applicable in the region of the concentration used for the appropriate threshold.

18

The uncertainty for modelling and objective estimation means the maximum deviation of the measured and calculated concentration levels, over the period for calculating the appropriate threshold, without taking into account the timing of events.

19

“Time coverage”(“yr amser a gwmpesir”) means the percentage of time considered for settling the threshold value during which the pollutant is measured.

20

“Data capture” (“y data a gipir”) means the ratio of the time for which the instrument produces valid data, to the time for which the statistical parameter or aggregated value is to be calculated.

SCHEDULE 9 — Reference methods

PART 1 — Group A pollutants

PART 2 — Group B pollutants in ambient air

PART 3 — Ozone

PART 4 — Other reference methods

SCHEDULE 10 — Ozone precursor substances

Objectives

1

The main objectives of measurements of ozone precursor substances are to analyse any trend in ozone precursors, to check the efficiency of emission reduction strategies, to check the consistency of emission inventories and to help attribute emission sources to pollution concentration.

2

An additional aim is to support the understanding of ozone formation and precursor dispersion processes, as well as the application of photochemical models.

Substances

3

Measurements of ozone precursor substances must include at least nitrogen oxides, and appropriate volatile organic compounds. For the purposes of this Schedule, “volatile organic compounds” means all organic compounds from anthropogenic and biogenic sources, other than methane, that are capable of producing photochemical oxidants by reaction with nitrogen oxides in the presence of sunlight.

4

A list of volatile organic compounds recommended for measurement by Directive 2002/3/EC[^f00014] is given in the table below—

Reference methods

5

The reference method for the analysis of oxides of nitrogen is ISO 7996:1985, Ambient air — determination of the mass concentrations of nitrogen oxides — chemiluminescence method.

Monitoring sites

6

Measurements should be taken in particular in urban and suburban areas at any monitoring site considered appropriate with regard to the monitoring objectives in this Schedule.

SCHEDULE 11 — Public information where alert or information thresholds are exceeded

PART 1 — Alert thresholds for nitrogen dioxide and sulphur dioxide

1

In cases where the alert thresholds for nitrogen dioxide or sulphur dioxide are exceeded, the information to be made available to the public should include at least—

• (a) the date, hour and place of the occurrence and the reasons for the occurrence, where known;

• (b) any forecasts of—

• (i) changes in concentration (improvement, stabilisation or deterioration), together with the reasons for those changes,

• (ii) the geographical area concerned, and

• (iii) the duration of the occurrence;

• (c) the type of population potentially sensitive to the occurrence; and

• (d) the precautions to be taken by the sensitive population concerned.

PART 2 — Alert and information thresholds for ozone

2

In cases where either the information threshold or the alert threshold for ozone—

• (a) is exceeded; or

• (b) is predicted to be exceeded,

the details set out in paragraphs 3 to 6 must, as a minimum, be made available to the public on a sufficiently large scale.

3

Information on any observed exceedance—

• (a) the location or area of the exceedance;

• (b) the type of threshold exceeded (information threshold or alert threshold);

• (c) the time at which the exceedance began and its duration; and

• (d) the highest 1-hour and 8-hour mean concentration.

4

Forecast for the following afternoon, day or days—

• (a) the geographical area of expected exceedances of an information threshold or alert threshold; and

• (b) the expected change in pollution, that is, improvement, stabilisation or deterioration.

5

Information on the type of population concerned, possible health effects and recommended conduct—

• (a) information on population groups at risk;

• (b) description of likely symptoms;

• (c) recommended precautions to be taken by the population concerned; and

• (d) where to find further information.

6

Information provided under this Schedule must also include—

• (a) information on preventive action to reduce pollution or exposure to it;

• (b) an indication of main source sectors; and

• (c) recommendations for action to reduce emissions.

SCHEDULE 12 — Collation of information and criteria for aggregating data and calculating statistical parameters

PART 1 — Information to be submitted to the Commission

1

The following information on ozone concentrations must be obtained and collated—

2

The National Assembly must also ensure that the following information is collated—

• (a) for ozone, nitrogen dioxide, oxides of nitrogen and the sums of ozone and nitrogen dioxide (added as parts per billion and expressed in μg/m³ ozone) the maximum, 99.9th, 98th and 50th percentiles and annual average and number of valid data from hourly series; and

• (b) the maximum, 98th and 50th percentile and annual average from a series of daily 8-hour ozone maxima.

3

Data compiled in monthly reports will be considered provisional and must be updated where necessary in subsequent submissions.

PART 2 — Criteria for aggregating data and calculating statistical parameters

4

In this Part, percentiles are to be calculated using the method specified in Council Decision 97/101/EC[^f00015] establishing a reciprocal exchange of information and data from networks and individual stations measuring ambient air pollution within member States.

5

The following criteria are to be used for checking validity when aggregating data and calculating statistical parameters—

SCHEDULE 13 — Revocations

Signed

Signed on behalf of the National Assembly for Wales under section 66(1) of the Government of Wales Act 1998[^f00010]

D. Elis-Thomas — The Presiding Officer of the National Assembly — 6 March 2007

Explanatory note

(This note is not part of the Regulations)

These Regulations apply in relation to Wales.

These Regulations—

• (a) implement Council Directive 96/62/EC on ambient air quality assessment and management (OJ No. L 296, 21.11.96, p.55);

• (b) implement Council Directive 1999/30/EC relating to limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead in ambient air (OJ No. L 163, 29.06.99, p.41);

• (c) implement Directive 2000/69/EC of the European Parliament and of the Council relating to limit values for benzene and carbon monoxide in ambient air (OJ No. L 313, 13.12.00, p.12);

• (d) implement Directive 2002/3/EC of the European Parliament and of the Council relating to ozone in ambient air (OJ No. L 67, 09.03.02, p.14);

• (e) implement Directive 2004/107/EC of the European Parliament and of the Council relating to arsenic, cadmium, mercury, nickel and polycyclic aromatic hydrocarbons in ambient air (OJ No. L 23, 26.01.05, p.3);

• (f) incorporate requirements imposed by Commission Decision 2001/744/EC amending Annex V to Council Directive 1999/30/EC (OJ No. L 278, 23.10.01, p.35) and Directive 2003/35/EC of the European Parliament and of the Council providing for public participation in respect of the drawing-up of certain plans and programmes relating to the environment and amending with regard to public participation and access to justice Council Directives 85/337/EEC and 96/61/EC (OJ No. L 156, 25.06.03, p.17); and

• (g) replace regulation 6 of the Air Quality Standards Regulations 1989 (S.I. 1989/317), the Air Quality Limit Values (Wales) Regulations 2002 (S.I. 2002/3183) (W.299), the Air Quality (Ozone) (Wales) Regulations 2003 (S.I. 2003/1848) (W.198) and the Air Quality Limit Values (Wales) (Amendment) Regulations 2005 (S.I. 2005/1157) (W.74), all of which are revoked by regulation 30 of, and Schedule 13 to, these Regulations.

Part 1 of these Regulations includes regulation 3, which designates the National Assembly for Wales (“the National Assembly”) as the competent authority for the purposes of article 3 (implementation and responsibilities) of Council Directive 96/62/EC.

Part 2 of these Regulations requires the attainment of air quality standards in respect of the concentration of various pollutants in ambient air.

For the purposes of Part 2, the National Assembly is required to divide Wales into zones within which the necessary air quality management and assessment takes place (regulation 5).

In accordance with regulation 6, limit values are imposed for “Group A” pollutants (benzene, carbon monoxide, lead, nitrogen dioxide and oxides of nitrogen, particulate matter (PM₁₀) and sulphur dioxide); target values are imposed for “Group B” pollutants (the content of arsenic, benzo(a)pyrene, cadmium and nickel, or their compounds, within the PM₁₀ fraction); and target values and long-term objectives are imposed for ozone.

Chapter 2 of Part 2 sets out the measures the National Assembly is required to take in order to ensure attainment of the relevant standards. The measures ordinarily required are those set out in regulation 7. In relation to benzene or nitrogen dioxide, where concentrations exceed the limit value plus the margin of tolerance specified, the National Assembly is required by regulation 8(2) to prepare and implement an improvement plan. The National Assembly is also required to prepare and implement an improvement plan by regulation 8(3) in cases where concentrations of ozone exceed the target value unless the National Assembly considers that the target value would not be attainable through proportionate measures. Finally, regulation 9 requires the National Assembly to take the measures specified in that regulation in cases where concentrations of Group B pollutants exceed the relevant target value or in cases where concentrations of ozone comply with the target value but exceed a long-term objective.

Regulation 10 requires the National Assembly to maintain compliance with the limit values and target values and, as far as the factors specified in that regulation permit, the long-term objective for ozone.

Regulation 11 requires the National Assembly to prepare and, to the extent it considers necessary, implement action plans which indicate the measures to be taken in cases where there is a risk that any limit value or the alert thresholds for nitrogen dioxide and sulphur dioxide will be exceeded. The National Assembly is also required to consider the preparation of action plans where there is a risk that the alert threshold for ozone will be exceeded.

Regulation 12 requires the National Assembly to assess the concentration of Group A pollutants, Group B pollutants and ozone within each zone.

Regulations 13 to 16 prescribe the assessment methods which are required or permitted (as the case may be) and the detailed requirements in relation to each method (for instance, requirements as to sampling points for fixed measurement).

In Part 3 of these Regulations, regulations 17 to 19 require the National Assembly to monitor or measure, respectively, PM2·5, ozone precursor substances and certain polycyclic aromatic hydrocarbons. Regulation 20 requires the taking of indicative measurements of the concentration and deposition of Group B pollutants, polycyclic aromatic hydrocarbons and mercury.

In Part 4 of these Regulations, regulations 21 to 25 require the National Assembly to disseminate up-to-date information to the public, including organisations representing relevant public interests. Regulation 26 requires the production of an annual report for ozone and regulation 27 requires action and improvement plans, and information as to their implementation, to be made available. Regulation 28 requires the National Assembly to ensure that the public can contribute to the development, modification and review of improvement plans.

In Part 5 of these Regulations, regulation 29 requires the National Assembly to obtain and collate data and regulation 30 provides for the repeal of Regulations that are superseded by these Regulations.

Footnotes

[^f00001]: S.I. 2000/2812.

[^f00002]: 1972 c. 68.

[^f00003]: OJ No L 296, 21.11.96, p.55.

[^f00004]: OJ No L 163, 29.06.99, p.41.

[^f00005]: OJ No L 313, 13.12.00, p.12.

[^f00006]: OJ No L 67, 09.03.02, p.14.

[^f00007]: OJ No L 23, 26.01.05, p.3.

[^f00008]: OJ No L 257, 10.10.96, p.26.

[^f00009]: The Directive is implemented by the Pollution Prevention and Control (England and Wales) Regulations 2000 (S.I. 2000/1973 as amended by S.I. 2001/503, 2002/275, 2002/1702, 2003/1699, 2003/3296, 2004/3276, 2005/1448 and 2006/2802 (W.241)).

[^f00010]: 1998 c. 38.

[^f00011]: OJ No L 125, 18.05.94, p.1.

[^f00012]: Copies of International Standards Organisation publications may be purchased from the British Standards Institution ('BSI') Sales Department either by telephone (0208 996 9001) or by post from the BSI, Standards House, 389 Chiswick High Road, London W4 4AL, http://www.bsi-global.com

[^f00013]: European Committee for Standardisation (“CEN”) publication; the address of CEN is 36, Rue de Stassart, B-1050, Brussels, Belgium http://www.cenorm.be

[^f00014]: A full reference for this Directive is given at regulation 2(2)(d).

[^f00015]: OJ L 35, 05.02.97, p.14.