Part I UPPER AND LOWER ASSESSMENT THRESHOLDSI1
Northern Ireland
The following upper and lower assessment thresholds will apply:
(a)
SULPHUR DIOXIDE
| Health protection | Ecosystem 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 limit value (12 μg/m3) |
| Lower assessment threshold | 40% of 24-hour limit value (50 μg/m3) not to be exceeded more than 3 times in any calendar year | 40% of winter limit value (8 μg/m3) |
(b)
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 limit value for the protection of vegetation (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 limit value (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 limit value (19.5 μg/m3) |
(c)
PARTICULATE MATTERf1
| 24-hour average | Annual average | |
|---|---|---|
| Upper assessment threshold | 60% of limit value (30 μg/m3) not to be exceeded more than 7 times in any calendar year | 70% of limit value (14 μg/m3) |
| Lower assessment threshold | 40% of limit value (20 μg/m3) not to be exceeded more than 7 times in any calendar year | 50% of limit value (10 μg/m3) |
| 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 | 50mg/m3 PM10 not to be exceeded more than 7 times a calendar year | To be derived from data and to be equivalent to Stage 1 limit value. | 1st January 2010 |
2 Annual limit value for the protection of human health | Calendar year | 20 mg/m3 PM10 | 50% on 1st January 2005 reducing every 12 months thereafter by equal annual percentages to reach 0% by 1st January 2010 | 1st January 2010 |
(d)
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) |
Annotations
Commencement
- I1
Sch. 2 Pt. I in operation at 1.5.2002, see reg. 1
Footnotes
- f1
-
The upper and lower assessment thresholds for PM10 are based on the following indicative limit values for 1 January 2010, which will be reviewed in the light of further information on health and environmental effects, technical feasibility and experience in the application of the existing “Stage 1” limit values