Technical Annual Status Report (Stage 2) for the CLRTAP Inventory Review: Synthesis and Assessment Country report
KEY CATEGORY ANALYSIS
Party: GB Submission year: 2026
Key categories analysis is becoming important in prioritising emission sources and identifying where inventory improvements can be most efficiently implemented. We have assessed the most important sources (the sources making up 80% of the national total) for your country, based on your latest submission. The key sources for the 2024, 2010 and 2005 emissions, including the corresponding percentages, are listed below. |
| Component | Year | Key categories (Sorted from high to low from left to right) | Total | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| NOx | 2024 | 1A3bi (18.1%) | 1A3bii (10.1%) | 1A1a (9.8%) | 1A2gviii (9.1%) | 1A3dii (7.9%) | 1A4ai (7.6%) | 1A1c (7.2%) | 1A4bi (4.4%) | 1A3biii (3.7%) | 1A1b (2.2%) | 80.1% | ||||||
| NMVOC | 2024 | 2D3a (22.8%) | 2H2 (16.8%) | 2D3d (7.1%) | 3Da2a (5.6%) | 3B1a (3.7%) | 3B1b (3.6%) | 2D3i (3.6%) | 1A4bi (3.3%) | 1B2av (3.1%) | 1B2b (2.8%) | 1B2ai (2.7%) | 1A3bv (2.3%) | 2D3g (2.2%) | 1A3bi (1.8%) | 81.2% | ||
| SOx | 2024 | 1A1b (23.7%) | 1A2gviii (16.1%) | 1A4bi (16.0%) | 1B1b (8.4%) | 1A1a (7.7%) | 2A6 (3.7%) | 1A2f (3.5%) | 1A4ai (3.2%) | 82.4% | ||||||||
| NH3 | 2024 | 3Da2a (21.3%) | 3Da1 (14.1%) | 3B1a (13.9%) | 3B1b (12.9%) | 3Da2c (8.1%) | 3Da3 (7.0%) | 6A (5.0%) | 82.2% | |||||||||
| PM2.5 | 2024 | 1A4bi (20.0%) | 1A3bvi (13.7%) | 5C2 (10.3%) | 1A2gviii (6.9%) | 1A3bvii (5.8%) | 2A5b (3.5%) | 1A3dii (3.1%) | 1A4ai (2.7%) | 5E (2.3%) | 2C1 (2.0%) | 1A3bi (2.0%) | 1A1a (1.9%) | 2I (1.6%) | 2G (1.6%) | 2A6 (1.5%) | 2A5a (1.5%) | 80.2% |
| PM10 | 2024 | 2A5b (17.7%) | 1A3bvi (13.5%) | 1A4bi (10.5%) | 2A5a (7.4%) | 3Dc (6.0%) | 5C2 (5.6%) | 1A3bvii (5.5%) | 1A2gviii (3.7%) | 3B4gii (2.1%) | 3B4giv (2.0%) | 2C1 (1.8%) | 1A3dii (1.7%) | 1A4ai (1.5%) | 5E (1.3%) | 80.3% | ||
| TSP | 2024 | 2A5b (33.0%) | 1A3bvi (9.7%) | 2A5a (8.5%) | 1A4bi (6.5%) | 1A3bvii (6.2%) | 3Dc (3.4%) | 3B4gi (3.3%) | 5C2 (3.2%) | 3B4giv (2.9%) | 3B4gii (2.4%) | 1A2gviii (2.1%) | 81.3% | |||||
| BC | 2024 | 1A4bi (18.6%) | 1A3bvi (15.7%) | 5C2 (12.3%) | 1A2gviii (6.6%) | 1A3bi (6.4%) | 1A4ai (5.6%) | 5E (5.4%) | 1A3dii (4.2%) | 1B1b (3.2%) | 1A3bii (2.9%) | 81.0% | ||||||
| CO | 2024 | 1A2gvii (26.1%) | 1A3bi (17.3%) | 1A4bi (14.6%) | 1A4bii (6.6%) | 1A3dii (4.1%) | 1A2a (4.0%) | 1A2gviii (3.2%) | 1A1a (3.1%) | 2C1 (2.6%) | 81.7% | |||||||
| Pb | 2024 | 1A3bvi (40.8%) | 2C1 (22.9%) | 1A3aii(i) (8.6%) | 1A2gviii (8.1%) | 80.4% | ||||||||||||
| Cd | 2024 | 2G (34.9%) | 1A2gviii (17.7%) | 1A4bi (12.2%) | 2C1 (9.1%) | 1A3bvi (4.6%) | 1A2d (4.3%) | 82.7% | ||||||||||
| Hg | 2024 | 1A1a (23.8%) | 5C1bv (11.0%) | 5A (9.9%) | 1A2f (9.1%) | 1A2gviii (8.8%) | 1A4bi (6.0%) | 2C1 (5.2%) | 1A3bi (4.3%) | 2C7c (4.0%) | 82.1% | |||||||
| As | 2024 | 5C2 (68.1%) | 2C1 (10.9%) | 1A2gviii (4.7%) | 83.7% | |||||||||||||
| Cr | 2024 | 1A3bvi (37.5%) | 5C2 (17.6%) | 2G (13.5%) | 2C1 (9.9%) | 1A1a (5.0%) | 83.5% | |||||||||||
| Cu | 2024 | 1A3bvi (58.5%) | 2G (38.7%) | 97.2% | ||||||||||||||
| Ni | 2024 | 1A4bi (46.4%) | 2G (12.7%) | 1A2gviii (10.4%) | 1A4ai (4.2%) | 1A1b (3.7%) | 2C1 (3.6%) | 81.2% | ||||||||||
| Se | 2024 | 1A1a (83.6%) | 83.6% | |||||||||||||||
| Zn | 2024 | 2G (27.9%) | 1A2gviii (27.2%) | 1A3bvi (24.0%) | 2C1 (8.6%) | 87.7% | ||||||||||||
| DIOX | 2024 | 1A4bi (21.8%) | 5C2 (19.6%) | 5E (15.3%) | 1A2gviii (12.7%) | 2C1 (5.7%) | 1A1a (4.3%) | 1A3bi (3.3%) | 82.6% | |||||||||
| PAH | 2024 | 1A4bi (86.7%) | 86.7% | |||||||||||||||
| HCB | 2024 | 1A1a (89.6%) | 89.6% | |||||||||||||||
| PCB | 2024 | 2K (36.8%) | 2C1 (22.2%) | 5C2 (19.6%) | 5E (19.4%) | 98.0% | ||||||||||||
| Component | Year | Key categories (Sorted from high to low from left to right) | Total | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| NOx | 2010 | 1A1a (21.2%) | 1A3bi (16.4%) | 1A3biii (15.2%) | 1A1c (5.6%) | 1A3bii (5.5%) | 1A3dii (4.2%) | 1A2gviii (4.1%) | 1A4cii (3.9%) | 1A4bi (3.8%) | 80.0% | |||||||||
| NMVOC | 2010 | 2D3a (18.0%) | 2H2 (9.6%) | 2D3d (8.9%) | 1A3bi (7.4%) | 1B2b (4.0%) | 2D3i (3.9%) | 1B2ai (3.7%) | 3Da2a (3.4%) | 3B1b (3.4%) | 1B2av (2.9%) | 1A4bi (2.9%) | 1B2c (2.8%) | 3B1a (2.6%) | 1B1a (2.6%) | 1A3bv (2.3%) | 1B2aiv (2.2%) | 80.7% | ||
| SOx | 2010 | 1A1a (41.6%) | 1A2gviii (16.7%) | 1A1b (13.9%) | 1B1b (4.6%) | 1A4bi (3.7%) | 80.4% | |||||||||||||
| NH3 | 2010 | 3Da2a (23.7%) | 3Da1 (15.6%) | 3B1b (14.9%) | 3B1a (11.5%) | 3Da3 (7.2%) | 1A3bi (4.5%) | 3B3 (4.4%) | 81.9% | |||||||||||
| PM2.5 | 2010 | 1A4bi (14.5%) | 1A3bvi (8.4%) | 1A3bi (6.7%) | 5C2 (6.4%) | 1A1a (5.3%) | 1A2gviii (4.6%) | 1A3bii (4.3%) | 1A4cii (4.0%) | 1A3biii (3.7%) | 1A3dii (3.6%) | 1A3bvii (3.4%) | 1A2gvii (3.2%) | 2C1 (3.1%) | 2A5b (2.8%) | 2G (2.5%) | 5E (1.9%) | 1A4ai (1.8%) | 80.3% | |
| PM10 | 2010 | 2A5b (16.1%) | 1A3bvi (9.2%) | 1A4bi (8.4%) | 2A5a (6.9%) | 1A1a (4.6%) | 3Dc (4.6%) | 1A3bi (3.8%) | 5C2 (3.8%) | 1A3bvii (3.6%) | 2C1 (3.2%) | 1A2gviii (2.9%) | 1A3bii (2.4%) | 1A4cii (2.3%) | 1A3dii (2.2%) | 1A3biii (2.1%) | 2G (1.8%) | 1A2gvii (1.8%) | 3B4giv (1.6%) | 81.3% |
| TSP | 2010 | 2A5b (31.6%) | 2A5a (8.4%) | 1A3bvi (6.9%) | 1A4bi (5.5%) | 1A3bvii (4.3%) | 1A1a (3.6%) | 2C1 (3.4%) | 3Dc (2.7%) | 5C2 (2.3%) | 3B4gi (2.3%) | 1A3bi (2.3%) | 3B4giv (2.1%) | 1A2gviii (1.8%) | 3B4gii (1.8%) | 3B3 (1.5%) | 80.6% | |||
| BC | 2010 | 1A3bi (19.8%) | 1A3bii (13.4%) | 1A4cii (10.0%) | 1A3biii (9.4%) | 1A2gvii (7.2%) | 1A3bvi (6.6%) | 1A4bi (6.3%) | 5C2 (5.4%) | 5E (3.0%) | 81.2% | |||||||||
| CO | 2010 | 1A3bi (38.3%) | 1A2gvii (13.3%) | 1A4bi (9.8%) | 1A2a (5.8%) | 1A1a (3.6%) | 1A4bii (3.4%) | 2C1 (3.3%) | 1A3bii (2.3%) | 1A3biii (2.1%) | 82.0% | |||||||||
| Pb | 2010 | 1A3bvi (36.5%) | 2C1 (16.5%) | 1A3aii(i) (10.5%) | 1A2gviii (9.4%) | 2G (6.9%) | 2C7c (2.9%) | 82.6% | ||||||||||||
| Cd | 2010 | 2G (40.9%) | 2C1 (13.6%) | 1A2gviii (10.8%) | 1A4bi (7.4%) | 1A3bvi (4.9%) | 1A1a (3.1%) | 80.6% | ||||||||||||
| Hg | 2010 | 1A1a (20.8%) | 5C1bv (12.0%) | 2B10a (11.5%) | 1A2gviii (9.3%) | 2C1 (5.3%) | 5A (5.1%) | 1A1b (4.4%) | 2C7c (3.8%) | 1A4bi (3.7%) | 1A2f (3.5%) | 1A2c (3.2%) | 82.6% | |||||||
| As | 2010 | 5C2 (52.9%) | 2C1 (21.1%) | 1A2gviii (6.5%) | 80.5% | |||||||||||||||
| Cr | 2010 | 1A3bvi (38.8%) | 5C2 (18.3%) | 2G (13.6%) | 2C7c (4.5%) | 2C1 (4.1%) | 1A1a (3.8%) | 83.1% | ||||||||||||
| Cu | 2010 | 1A3bvi (58.5%) | 2G (37.6%) | 96.0% | ||||||||||||||||
| Ni | 2010 | 1A2gviii (33.7%) | 2G (11.3%) | 1A4bi (8.0%) | 1A3dii (7.9%) | 1A4ai (7.1%) | 1A1b (6.0%) | 1A3bvi (2.9%) | 1A1a (2.8%) | 2C1 (2.8%) | 82.7% | |||||||||
| Se | 2010 | 1A1a (37.8%) | 2A3 (28.8%) | 2G (8.2%) | 2C1 (5.9%) | 80.6% | ||||||||||||||
| Zn | 2010 | 1A2gviii (29.1%) | 2G (25.5%) | 1A3bvi (21.6%) | 2C1 (13.2%) | 89.4% | ||||||||||||||
| DIOX | 2010 | 2C1 (29.2%) | 5E (15.5%) | 5C2 (14.2%) | 1A2gviii (8.9%) | 1A3bi (7.8%) | 1A4bi (6.0%) | 81.6% | ||||||||||||
| PAH | 2010 | 1A4bi (78.4%) | 5C2 (4.8%) | 83.1% | ||||||||||||||||
| HCB | 2010 | 3Df (66.8%) | 1A1a (24.9%) | 91.7% | ||||||||||||||||
| PCB | 2010 | 2K (73.0%) | 2C1 (11.5%) | 84.5% | ||||||||||||||||
| Component | Year | Key categories (Sorted from high to low from left to right) | Total | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| NOx | 2005 | 1A1a (23.7%) | 1A3bi (17.8%) | 1A3biii (15.0%) | 1A1c (4.6%) | 1A2gviii (4.5%) | 1A3bii (4.3%) | 1A3dii (3.9%) | 1A4ai (3.4%) | 1A4cii (3.3%) | 80.6% | ||||||||||
| NMVOC | 2005 | 2D3a (12.6%) | 1A3bi (12.2%) | 2D3d (10.0%) | 1B2ai (7.0%) | 2H2 (6.8%) | 1B2av (4.0%) | 1B2b (3.8%) | 1A3bv (3.6%) | 2D3i (3.4%) | 2B10a (3.0%) | 3B1b (2.7%) | 1B2aiv (2.6%) | 3Da2a (2.5%) | 1B1a (2.5%) | 1A4bi (2.1%) | 3B1a (1.9%) | 80.7% | |||
| SOx | 2005 | 1A1a (53.9%) | 1A1b (10.5%) | 1A2gviii (9.9%) | 1A3dii (4.7%) | 1A4bi (3.0%) | 82.0% | ||||||||||||||
| NH3 | 2005 | 3Da2a (24.1%) | 3B1b (14.7%) | 3Da1 (13.3%) | 3B1a (10.2%) | 3Da3 (7.5%) | 1A3bi (6.2%) | 3B3 (5.2%) | 81.2% | ||||||||||||
| PM2.5 | 2005 | 1A4bi (11.9%) | 1A3bvi (6.7%) | 1A3bi (5.9%) | 1A1a (5.8%) | 1A3biii (5.6%) | 1A3dii (5.1%) | 5C2 (4.9%) | 1A3bii (4.7%) | 1A2gvii (4.6%) | 1A4cii (4.3%) | 1A2gviii (3.7%) | 2C1 (3.2%) | 1A3bvii (2.8%) | 2G (2.5%) | 2A5b (2.4%) | 5E (2.1%) | 1A4ai (1.9%) | 2A6 (1.9%) | 80.3% | |
| PM10 | 2005 | 2A5b (13.9%) | 2A5a (8.1%) | 1A3bvi (7.6%) | 1A4bi (7.1%) | 1A1a (5.7%) | 3Dc (3.8%) | 1A3bi (3.5%) | 2C1 (3.4%) | 1A3biii (3.3%) | 1A3dii (3.2%) | 5C2 (3.0%) | 1A3bvii (3.0%) | 1A3bii (2.8%) | 1A2gvii (2.7%) | 1A4cii (2.5%) | 1A2gviii (2.4%) | 2G (2.0%) | 2A6 (1.8%) | 5E (1.3%) | 81.0% |
| TSP | 2005 | 2A5b (28.2%) | 2A5a (10.2%) | 1A3bvi (5.9%) | 1A4bi (4.8%) | 1A1a (4.7%) | 1A3bvii (3.7%) | 2C1 (3.6%) | 3Dc (2.3%) | 1A3bi (2.1%) | 3B4gi (2.0%) | 1A3biii (2.0%) | 1A3dii (2.0%) | 5C2 (1.9%) | 3B4giv (1.8%) | 1A3bii (1.7%) | 1A2gvii (1.6%) | 3B4gii (1.6%) | 80.4% | ||
| BC | 2005 | 1A3bi (15.3%) | 1A3bii (13.1%) | 1A3biii (12.9%) | 1A4cii (10.1%) | 1A2gvii (9.9%) | 1A3bvi (5.2%) | 1A4bi (5.0%) | 5C2 (4.3%) | 1A2gviii (3.9%) | 5E (3.2%) | 82.8% | |||||||||
| CO | 2005 | 1A3bi (45.5%) | 1A2gvii (13.8%) | 1A2a (7.4%) | 1A4bi (6.5%) | 1A3bii (2.8%) | 2C1 (2.7%) | 1A3biv (2.4%) | 81.1% | ||||||||||||
| Pb | 2005 | 1A3bvi (24.0%) | 2C1 (20.0%) | 1A3aii(i) (16.8%) | 2G (7.3%) | 2B10a (6.6%) | 1A2gviii (5.6%) | 80.3% | |||||||||||||
| Cd | 2005 | 2G (32.6%) | 2C1 (16.7%) | 1A1a (15.1%) | 1A2gviii (7.5%) | 1A4bi (6.2%) | 1A3bvi (3.9%) | 82.0% | |||||||||||||
| Hg | 2005 | 1A1a (28.2%) | 2B10a (14.0%) | 5C1bv (11.2%) | 2C1 (5.9%) | 1A2gviii (5.7%) | 2C7c (5.6%) | 5A (4.6%) | 1A4bi (3.8%) | 1A2f (3.7%) | 82.6% | ||||||||||
| As | 2005 | 5C2 (47.3%) | 2C1 (27.1%) | 1A2gviii (5.3%) | 1A4bi (3.5%) | 83.2% | |||||||||||||||
| Cr | 2005 | 1A3bvi (29.5%) | 2B10a (15.0%) | 5C2 (13.7%) | 2G (10.4%) | 1A1a (6.8%) | 2C1 (5.9%) | 81.3% | |||||||||||||
| Cu | 2005 | 1A3bvi (57.9%) | 2G (37.3%) | 95.1% | |||||||||||||||||
| Ni | 2005 | 1A2gviii (27.1%) | 1A4bi (25.7%) | 1A3dii (9.1%) | 2G (7.3%) | 1A1b (5.8%) | 1A1a (3.6%) | 2C3 (2.5%) | 81.1% | ||||||||||||
| Se | 2005 | 1A1a (44.1%) | 2A3 (33.3%) | 2C1 (5.7%) | 83.1% | ||||||||||||||||
| Zn | 2005 | 1A2gviii (25.7%) | 2G (24.3%) | 1A3bvi (20.5%) | 2C1 (17.6%) | 88.1% | |||||||||||||||
| DIOX | 2005 | 5C2 (25.9%) | 5E (22.4%) | 2C1 (18.6%) | 1A3bi (6.5%) | 1A4bi (5.9%) | 1A1a (3.8%) | 83.2% | |||||||||||||
| PAH | 2005 | 1A4bi (62.6%) | 5C2 (21.9%) | 84.5% | |||||||||||||||||
| HCB | 2005 | 3Df (54.4%) | 2B10a (33.0%) | 87.3% | |||||||||||||||||
| PCB | 2005 | 2K (80.9%) | 80.9% | ||||||||||||||||||