The Air Quality Limit Values (Scotland) Regulations 2003 No. 428

Regulations 2, 4(1), 10(2), (3), 11(1),(3), 14(12), (13)

SCHEDULE 1 LIMIT VALUES, MARGINS OF TOLERANCE, INFORMATION AND ALERT THRESHOLDS

PART I SULPHUR DIOXIDE

Limit values for sulphur dioxide

1.1  

	Averaging period	Limit value	Margin of tolerance (a)	Date by which limit value is to be met
1.  Hourly limit value for the protection of human health	1 hour	350 μg/m3, not to be exceeded more than 24 times a calendar year	60 μg/m3, reducing to 30μg/m3 on 1st January 2004 and to 0 μg/m3 on 1st January 2005	1st January 2005
2.  Daily limit value for the protection of human health	24 hours	125 μg/m3, not to be exceeded more than 3 times a calendar year	None	1st January 2005

Alert threshold for sulphur dioxide

1.2  500 μg/m³ measured over three consecutive hours at locations representative of air quality over at least 100 km2 or an entire zone, whichever is the smaller.

Minimum details to be made available to the public when the alert threshold for sulphur dioxide is exceeded

1.3  Details 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 II NITROGEN DIOXIDE (NO₂) AND OXIDES OF NITROGEN (NO_x)

Limit values for nitrogen dioxide and oxides of nitrogen

2.1  

	Averaging period	Limit value	Margin of tolerance	Date by which limit value is to be met
1.  Hourly limit value for the protection of human health	1 hour	200 μg/m3 NO2, not to be exceeded more than 18 times a calendar year	70 μg/m3, reducing on 1st January 2004 and on 1st January of each following year by equal annual amounts to reach 0 μg/m3 by 1st January 2010	1st January 2010
2.  Annual limit value for the protection of human health	Calendar year	40 μg/m3 NO2	14 μg/m3, reducing on 1st January 2004 and on 1st January of each following year by equal annual amounts to reach 0 μg/m3 by 1st January 2010	1st January 2010

Alert threshold for nitrogen dioxide

2.2  400 μg/m³ measured over three consecutive hours at locations representative of air quality over at least 100 km² or an entire zone or agglomeration, whichever is the smaller.

Minimum details to be made available to the public when the alert threshold for nitrogen dioxide is exceeded

2.3  Details 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 III PARTICULATE MATTER (PM₁₀)

	Averaging period	Limit value	Margin of tolerance	Date by which limit value is to be met
1.  24-hour limit value for the protection of human health	24 hours	50 μg/m3 PM10, not to be exceeded more than 35 times a calendar year	10 μg/m3 , reducing on 1st January 2004 to 5 μg/m3 and on 1st January 2005 to 0 μg/m3.	1st January 2005
2.  Annual limit value for the protection of human health	Calendar year	40 μ g/m3 PM10	3.2 μg/m3, reducing on 1st January 2004 to 1.6μg/m3 and on 1st January 2005 to 0 μg/m3	1st January 2005

PART IV LEAD

	Averaging period	Limit value	Margin of tolerance	Date by which limit value is to be met
Annual limit value for the protection of human health	Calendar year	0.5 μg/m3	0.2 μg/m3, reducing on 1st January 2004 to 0.1μg/m3 and on 1st January 2005 to 0 μg/m3	1st January 2005

PART V BENZENE

	Averaging period	Limit value	Margin of tolerance	Date by which limit value is to be met
Limit value for the protection of human health	Calendar year	5μg/m3	5μg/m3 reducing on 1st January 2006 and every 12 months thereafter by 1 μg/m3 to reach 0 μg/m3 by 1st January 2010	1st January 2010

PART VI CARBON MONOXIDE

6.1  

	Averaging period	Limit value	Margin of tolerance	Date by which limit value is to be met
Limit value for the protection of human health	Maximum daily 8-hour mean	10mg/m3	4 mg/m3 reducing on 1st January 2004 to 2 mg/m3, and to 0 mg/m3 on 1st January 2005	1st January 2005

6.2  The maximum daily 8-hour mean concentration shall be selected by examining 8-hour running averages, calculated from hourly data and updated each hour. Each 8-hour average so calculated shall be assigned to the day on which it ends, i.e. the first calculation period for any one day shall be the period from 17:00 on the previous day to 0100 on that day; the last calculation period for any one day shall be the period from 1600 to 2400 on that day.

PART VII OZONE

Information and alert thresholds for ozone

7.1.  

	Parameter	Threshold
(a) The exceedance of the threshold is to be measured or predicted for three consecutive hours.
Information threshold	1 hour average	180μg/m3
Alert threshold	1 hour average(a)	240μg/m3

Minimum details to be supplied to the public when the information or alert threshold is exceeded or exceedance is predicted

7.2.  Details to be supplied to the public on a sufficiently large scale as soon as possible should include the following.

1.  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.

2.  Forecast for the following afternoon, day or days–

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

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

3.  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.

4.  Information provided under this Schedule shall 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.