O3, last 14 days

O₃ concentrations per day (µg/m³), 30/03/2026 - 12/04/2026

Highest hourly meanHighest 8-hourly mean

- Click on the figures in the table cells to get an evolution graph of daily concentrations
- Click on the date to get an interpolation map
- "NA" means no or not enough data were available

Code city 30/03 31/03 01/04 02/04 03/04 04/04 05/04 06/04 07/04 08/04 09/04 10/04 11/04 12/04

41B011 Sint-Agatha-Berchem 85.5 75 84.5 78 81 75 85.5 91.5 103.5 100.5 102 80 84 67

41MEU1 Neder-Over-Heembeek 87 75.5 86 76.5 72.5 69.5 81 91 108 102 102.5 80.5 88.5 71.5

41N043 Voorhaven (Haren) 84.5 71.5 74 65 68.5 66.5 77.5 84 99.5 94.5 98.5 75.5 80 68

41R001 Sint-Jans-Molenbeek 75 60.5 66.5 62 70 66 76.5 80.5 96.5 89.5 94 71.5 82 66

41R012 Ukkel 81 74.5 83.5 76.5 78.5 75 86 89 108.5 102 108.5 82 90 74

42N016 Dessel 87.5 83 93 79.5 87 82 84.5 98 100 107.5 112 84 95 78

42N027 Bree 87.5 80.5 69 73.5 77 NA NA NA 93 101.5 112 83 94.5 83.5

42N035 Aarschot 89 83 92.5 78 87.5 83.5 89 97.5 107 125.5 120.5 83.5 94.5 79

42N040 Sint-Pieters-Leeuw 84 71.5 85.5 75 77.5 73.5 83 95.5 106.5 107 106 84 85.5 70

42N046 Gellik 89 68.5 82.5 67 84 82.5 88.5 95.5 97 98.5 114 84 95.5 83.5

42N047 Hasselt 85.5 81.5 86.5 79 84.5 82 89 97 100.5 120 116.5 83 94 81.5

42R801 Borgerhout 87.5 72 89 78 79.5 77.5 85.5 97.5 100 112.5 111 84 87.5 79.5

42R811 Schoten 89.5 83.5 102 82.5 81 81.5 86.5 98.5 104.5 118 117 83.5 93 81

42R842 Mechelen (Hendrik Speecqvest) 84 72.5 83 74 81 72.5 81.5 89.5 99.5 105.5 97 80.5 89.5 76.5

44M705 Roeselare (Haven) 86.5 82 NA 44 83 85.5 86.5 90.5 109 110 106 91 95.5 82

44N012 Moerkerke 88 NA 75 83.5 79.5 80.5 85.5 96 96 103.5 96 88.5 92 78.5

44N029 Houtem (Veurne) 88.5 81.5 63.5 85.5 75 76.5 82.5 90.5 100 112.5 101 90 86 79

44R701 Gent (Baudelopark) 86 73 83 81.5 75.5 77.5 88.5 97 103 112.5 108 86 85.5 80

44R710 Destelbergen 87 77 86 82.5 78 80 90 97 106 114 112.5 85 89.5 82

43N060 Havinnes 72.5 66 71 72.5 64 67.5 70.5 84.5 90 108 100 80.5 78.5 68.5

43N064 Rixensart 91 79 93 82 85.5 75.5 90 96 107 106 112 87 96 74.5

43N066 Eupen 78.5 70.5 85.5 66 83.5 74.5 82.5 86.5 98 89.5 100.5 78 92 78.5

43N070 Mons 81 70 81.5 77.5 69 64 78.5 90.5 96 111 94 81.5 75 56

43N073 Vezin 83 80 87.5 69 81 76.5 83.5 90 98.5 99.5 102 83.5 93.5 79

43N085 Vielsalm 72.5 71 84 72 76 65.5 83.5 88 96 95.5 101.5 85 91.5 80

43N093 Sinsin 86.5 84.5 85 66 81 77 88.5 90 96 98.5 104 88 89.5 81.5

43N100 Dourbes 89 93.5 97 76 86 79.5 93.5 94.5 108.5 110 112.5 92 96.5 87.5

43N113 Saint-Ode 86.5 87.5 89.5 86 82.5 74 92.5 87 98 96 104 86.5 86 82

43N121 Offagne 74.5 68 69.5 68.5 69.5 47.5 86 62.5 84.5 71.5 89 65 80 68

43N132 Habay-La-Neuve 82 85 87 79.5 77.5 66 80.5 91 98 92 102.5 84 79.5 80.5

43R221 Herstal 84.5 71 85.5 61 80 74.5 86.5 89.5 98 93 113.5 84 95.5 88.5

43R222 Liège (ISSeP) 84.5 74.5 84 59 84 78 88 92 100.5 98 108 84.5 97.5 81.5

43R240 Engis 77 75.5 78 56 79.5 73.5 83.5 88.5 98.5 88.5 105 81.5 91 76.5

43R401 Namur 84 80.5 85 65.5 80.5 77.5 87.5 89 90.5 94.5 102.5 87.5 91 80

45R502 Lodelinsart 77.5 68 81 66 72 66.5 77.5 84.5 91 100 95.5 78 89 65.5

Interpolated spatial average in :

Brussels 84 72 81 73 76 71 82 89 102 99 102 79 86 70

Flanders 87 78 82 78 80 79 85 95 101 108 105 85 90 78

Wallonia 81 77 83 69 77 70 83 87 95 96 100 82 86 74

Belgium 84 78 83 73 79 74 84 91 98 101 102 83 88 76

% of the population exposed to O₃ concentrations > 180 μg/m³ in:

Brussels 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%

Flanders 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%

Wallonia 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%

Belgium 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%

% of the population exposed to O₃ concentrations > 240 μg/m³ in:

Brussels 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%

Flanders 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%

Wallonia 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%

Belgium 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%

Code	city	30/03	31/03	01/04	02/04	03/04	04/04	05/04	06/04	07/04	08/04	09/04	10/04	11/04	12/04
41B011	Sint-Agatha-Berchem	85.5	75	84.5	78	81	75	85.5	91.5	103.5	100.5	102	80	84	67
41MEU1	Neder-Over-Heembeek	87	75.5	86	76.5	72.5	69.5	81	91	108	102	102.5	80.5	88.5	71.5
41N043	Voorhaven (Haren)	84.5	71.5	74	65	68.5	66.5	77.5	84	99.5	94.5	98.5	75.5	80	68
41R001	Sint-Jans-Molenbeek	75	60.5	66.5	62	70	66	76.5	80.5	96.5	89.5	94	71.5	82	66
41R012	Ukkel	81	74.5	83.5	76.5	78.5	75	86	89	108.5	102	108.5	82	90	74
42N016	Dessel	87.5	83	93	79.5	87	82	84.5	98	100	107.5	112	84	95	78
42N027	Bree	87.5	80.5	69	73.5	77	NA	NA	NA	93	101.5	112	83	94.5	83.5
42N035	Aarschot	89	83	92.5	78	87.5	83.5	89	97.5	107	125.5	120.5	83.5	94.5	79
42N040	Sint-Pieters-Leeuw	84	71.5	85.5	75	77.5	73.5	83	95.5	106.5	107	106	84	85.5	70
42N046	Gellik	89	68.5	82.5	67	84	82.5	88.5	95.5	97	98.5	114	84	95.5	83.5
42N047	Hasselt	85.5	81.5	86.5	79	84.5	82	89	97	100.5	120	116.5	83	94	81.5
42R801	Borgerhout	87.5	72	89	78	79.5	77.5	85.5	97.5	100	112.5	111	84	87.5	79.5
42R811	Schoten	89.5	83.5	102	82.5	81	81.5	86.5	98.5	104.5	118	117	83.5	93	81
42R842	Mechelen (Hendrik Speecqvest)	84	72.5	83	74	81	72.5	81.5	89.5	99.5	105.5	97	80.5	89.5	76.5
44M705	Roeselare (Haven)	86.5	82	NA	44	83	85.5	86.5	90.5	109	110	106	91	95.5	82
44N012	Moerkerke	88	NA	75	83.5	79.5	80.5	85.5	96	96	103.5	96	88.5	92	78.5
44N029	Houtem (Veurne)	88.5	81.5	63.5	85.5	75	76.5	82.5	90.5	100	112.5	101	90	86	79
44R701	Gent (Baudelopark)	86	73	83	81.5	75.5	77.5	88.5	97	103	112.5	108	86	85.5	80
44R710	Destelbergen	87	77	86	82.5	78	80	90	97	106	114	112.5	85	89.5	82
43N060	Havinnes	72.5	66	71	72.5	64	67.5	70.5	84.5	90	108	100	80.5	78.5	68.5
43N064	Rixensart	91	79	93	82	85.5	75.5	90	96	107	106	112	87	96	74.5
43N066	Eupen	78.5	70.5	85.5	66	83.5	74.5	82.5	86.5	98	89.5	100.5	78	92	78.5
43N070	Mons	81	70	81.5	77.5	69	64	78.5	90.5	96	111	94	81.5	75	56
43N073	Vezin	83	80	87.5	69	81	76.5	83.5	90	98.5	99.5	102	83.5	93.5	79
43N085	Vielsalm	72.5	71	84	72	76	65.5	83.5	88	96	95.5	101.5	85	91.5	80
43N093	Sinsin	86.5	84.5	85	66	81	77	88.5	90	96	98.5	104	88	89.5	81.5
43N100	Dourbes	89	93.5	97	76	86	79.5	93.5	94.5	108.5	110	112.5	92	96.5	87.5
43N113	Saint-Ode	86.5	87.5	89.5	86	82.5	74	92.5	87	98	96	104	86.5	86	82
43N121	Offagne	74.5	68	69.5	68.5	69.5	47.5	86	62.5	84.5	71.5	89	65	80	68
43N132	Habay-La-Neuve	82	85	87	79.5	77.5	66	80.5	91	98	92	102.5	84	79.5	80.5
43R221	Herstal	84.5	71	85.5	61	80	74.5	86.5	89.5	98	93	113.5	84	95.5	88.5
43R222	Liège (ISSeP)	84.5	74.5	84	59	84	78	88	92	100.5	98	108	84.5	97.5	81.5
43R240	Engis	77	75.5	78	56	79.5	73.5	83.5	88.5	98.5	88.5	105	81.5	91	76.5
43R401	Namur	84	80.5	85	65.5	80.5	77.5	87.5	89	90.5	94.5	102.5	87.5	91	80
45R502	Lodelinsart	77.5	68	81	66	72	66.5	77.5	84.5	91	100	95.5	78	89	65.5

Interpolated spatial average in :
Brussels	84	72	81	73	76	71	82	89	102	99	102	79	86	70
Flanders	87	78	82	78	80	79	85	95	101	108	105	85	90	78
Wallonia	81	77	83	69	77	70	83	87	95	96	100	82	86	74
Belgium	84	78	83	73	79	74	84	91	98	101	102	83	88	76

% of the population exposed to O₃ concentrations > 180 μg/m³ in:
Brussels	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
Flanders	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
Wallonia	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
Belgium	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%

% of the population exposed to O₃ concentrations > 240 μg/m³ in:
Brussels	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
Flanders	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
Wallonia	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
Belgium	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%

Color legend: Kleurlegende

These data are not validated : they should not be used for any study whatsoever
The use or publication of the data is allowed only when the source (www.irceline.be) is acknowledged