O3, last 14 days

O₃ concentrations per day (µg/m³), 22/06/2026 - 05/07/2026

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
[O₃]"ozone day" : day with at least one exceedance in Belgium of the EU threshold for information of the public (180 μg/m3)

Code city 22/06 23/06 24/06[O₃]
25/06[O₃]
26/06[O₃]
27/06[O₃]
28/06 29/06 30/06 01/07 02/07 03/07 04/07 05/07

41B011 Sint-Agatha-Berchem 126 129 147.5 204.5 162.5 167 102.5 102.5 75 92.5 67 98.5 94 55

41MEU1 Neder-Over-Heembeek 116 124.5 148 167.5 155.5 NA NA 103 73.5 94.5 64.5 98.5 92 52.5

41N043 Voorhaven (Haren) 118 115.5 145 177 161 162 95 97 69 87.5 59.5 90.5 85.5 46.5

41R001 Sint-Jans-Molenbeek 124 115.5 155.5 197 154.5 170 100.5 96.5 70.5 83.5 62.5 88.5 85.5 49

41R012 Ukkel 125 113 137.5 193 157.5 177 101.5 102 74.5 93.5 64.5 99 90.5 54.5

42N016 Dessel 134.5 135 155 191 185.5 201.5 125 107.5 100.5 111.5 75 102.5 110 50.5

42N027 Bree 129.5 128.5 181.5 196 167.5 216 129.5 61.5 113 121.5 80 120.5 112.5 53

42N035 Aarschot 131.5 141.5 142 202.5 194 203.5 122.5 129 107 109.5 71.5 110 104 60.5

42N040 Sint-Pieters-Leeuw 122 119 140.5 192 157 164.5 100.5 99.5 76 91 65.5 97 91 53.5

42N046 Gellik 137 129.5 161.5 191.5 157 221 118.5 129.5 113 114.5 70 121.5 104.5 57.5

42N047 Hasselt 128.5 139 143 212.5 164.5 221 117.5 116.5 111 118 72.5 117 106 56

42R801 Borgerhout 122 126.5 170 185.5 193 171 102 98.5 NA 86.5 75.5 92.5 98 54

42R811 Schoten 124.5 135 169.5 196 208 174 112 102 71 92 73 96 103 49.5

42R842 Mechelen (Hendrik Speecqvest) 119 116 158.5 176.5 173.5 167 95.5 97.5 81 94.5 64 91 93.5 53

44M705 Roeselare (Haven) 154.5 126 184 214.5 154.5 128 93 92.5 73 92.5 76 86 84 74

44N012 Moerkerke 119.5 145.5 188 207.5 170.5 106.5 92 81.5 72 85 82.5 85 90 64

44N029 Houtem (Veurne) 113.5 128 204 171.5 146.5 105 104.5 86 64 77.5 81.5 85.5 81.5 73

44R701 Gent (Baudelopark) 153 150 161.5 222.5 173.5 131.5 101.5 93.5 76.5 91 73.5 89 90 61.5

44R710 Destelbergen 153 150 153.5 206 173.5 138 101 93.5 72.5 94 71 91.5 94.5 60.5

43N060 Havinnes NA NA NA 177.5 151.5 137.5 92 104 68 88.5 75 89.5 83.5 68

43N064 Rixensart 108.5 98 125 191.5 166.5 192.5 113 113.5 90.5 101.5 73.5 107.5 98 57.5

43N066 Eupen 155 127 159.5 190.5 155.5 NA 175.5 NA NA NA NA NA NA NA

43N070 Mons 120 107.5 117 176.5 134 195.5 65.5 93.5 70.5 86.5 55 86 74 58

43N073 Vezin 131 135.5 127 215.5 151 217.5 109 113.5 99 106 64 106.5 97 53.5

43N085 Vielsalm 132 103 133 157 143.5 138.5 124.5 100.5 121 104.5 75.5 102 103 51.5

43N093 Sinsin 145 116 125.5 198.5 137.5 167.5 119 110 110.5 111.5 68 111 98.5 61.5

43N100 Dourbes NA 108.5 127.5 141 146.5 193 116 110 114.5 107.5 72.5 117 105.5 75

43N113 Saint-Ode 122 108.5 116.5 134.5 139.5 132.5 121.5 105 124.5 113.5 81.5 111.5 98 63

43N121 Offagne 128 111.5 113 136 131.5 129.5 115.5 95.5 115 101.5 68 109.5 96.5 65

43N132 Habay-La-Neuve 119 101.5 118.5 134 139 133 118.5 100 108 102.5 71.5 98.5 95.5 60

43R221 Herstal 150 127.5 146.5 195 155 203.5 NA 128.5 111 122 66.5 115.5 101.5 59

43R222 Liège (ISSeP) NA NA NA NA 154.5 121.5 NA NA NA NA NA NA NA NA

43R240 Engis 129 163.5 149.5 200.5 175 208.5 123.5 115 99 110.5 63 112 96.5 52.5

43R401 Namur 120 140.5 125.5 194 157.5 189.5 109 112 100 100 63.5 108.5 99 57.5

45R502 Lodelinsart 115 108 128 201 157.5 209 98 97.5 NA NA NA NA NA NA

Interpolated spatial average in :

Brussels 120 114 136 182 156 169 101 102 76 91 65 96 90 53

Flanders 128 129 156 190 161 159 102 100 83 96 73 97 95 59

Wallonia 124 108 124 164 139 156 110 101 100 101 67 104 95 60

Belgium 126 118 139 176 149 158 106 101 92 99 70 101 95 59

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

Brussels 0% 0% 0% 67% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%

Flanders 0% 0% 5% 92% 12% 29% 0% 0% 0% 0% 0% 0% 0% 0%

Wallonia 0% 0% 0% 57% <1% 48% 0% 0% 0% 0% 0% 0% 0% 0%

Belgium 0% 0% 3% 78% 7% 33% 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	22/06	23/06	24/06[O₃]	25/06[O₃]	26/06[O₃]	27/06[O₃]	28/06	29/06	30/06	01/07	02/07	03/07	04/07	05/07
41B011	Sint-Agatha-Berchem	126	129	147.5	204.5	162.5	167	102.5	102.5	75	92.5	67	98.5	94	55
41MEU1	Neder-Over-Heembeek	116	124.5	148	167.5	155.5	NA	NA	103	73.5	94.5	64.5	98.5	92	52.5
41N043	Voorhaven (Haren)	118	115.5	145	177	161	162	95	97	69	87.5	59.5	90.5	85.5	46.5
41R001	Sint-Jans-Molenbeek	124	115.5	155.5	197	154.5	170	100.5	96.5	70.5	83.5	62.5	88.5	85.5	49
41R012	Ukkel	125	113	137.5	193	157.5	177	101.5	102	74.5	93.5	64.5	99	90.5	54.5
42N016	Dessel	134.5	135	155	191	185.5	201.5	125	107.5	100.5	111.5	75	102.5	110	50.5
42N027	Bree	129.5	128.5	181.5	196	167.5	216	129.5	61.5	113	121.5	80	120.5	112.5	53
42N035	Aarschot	131.5	141.5	142	202.5	194	203.5	122.5	129	107	109.5	71.5	110	104	60.5
42N040	Sint-Pieters-Leeuw	122	119	140.5	192	157	164.5	100.5	99.5	76	91	65.5	97	91	53.5
42N046	Gellik	137	129.5	161.5	191.5	157	221	118.5	129.5	113	114.5	70	121.5	104.5	57.5
42N047	Hasselt	128.5	139	143	212.5	164.5	221	117.5	116.5	111	118	72.5	117	106	56
42R801	Borgerhout	122	126.5	170	185.5	193	171	102	98.5	NA	86.5	75.5	92.5	98	54
42R811	Schoten	124.5	135	169.5	196	208	174	112	102	71	92	73	96	103	49.5
42R842	Mechelen (Hendrik Speecqvest)	119	116	158.5	176.5	173.5	167	95.5	97.5	81	94.5	64	91	93.5	53
44M705	Roeselare (Haven)	154.5	126	184	214.5	154.5	128	93	92.5	73	92.5	76	86	84	74
44N012	Moerkerke	119.5	145.5	188	207.5	170.5	106.5	92	81.5	72	85	82.5	85	90	64
44N029	Houtem (Veurne)	113.5	128	204	171.5	146.5	105	104.5	86	64	77.5	81.5	85.5	81.5	73
44R701	Gent (Baudelopark)	153	150	161.5	222.5	173.5	131.5	101.5	93.5	76.5	91	73.5	89	90	61.5
44R710	Destelbergen	153	150	153.5	206	173.5	138	101	93.5	72.5	94	71	91.5	94.5	60.5
43N060	Havinnes	NA	NA	NA	177.5	151.5	137.5	92	104	68	88.5	75	89.5	83.5	68
43N064	Rixensart	108.5	98	125	191.5	166.5	192.5	113	113.5	90.5	101.5	73.5	107.5	98	57.5
43N066	Eupen	155	127	159.5	190.5	155.5	NA	175.5	NA	NA	NA	NA	NA	NA	NA
43N070	Mons	120	107.5	117	176.5	134	195.5	65.5	93.5	70.5	86.5	55	86	74	58
43N073	Vezin	131	135.5	127	215.5	151	217.5	109	113.5	99	106	64	106.5	97	53.5
43N085	Vielsalm	132	103	133	157	143.5	138.5	124.5	100.5	121	104.5	75.5	102	103	51.5
43N093	Sinsin	145	116	125.5	198.5	137.5	167.5	119	110	110.5	111.5	68	111	98.5	61.5
43N100	Dourbes	NA	108.5	127.5	141	146.5	193	116	110	114.5	107.5	72.5	117	105.5	75
43N113	Saint-Ode	122	108.5	116.5	134.5	139.5	132.5	121.5	105	124.5	113.5	81.5	111.5	98	63
43N121	Offagne	128	111.5	113	136	131.5	129.5	115.5	95.5	115	101.5	68	109.5	96.5	65
43N132	Habay-La-Neuve	119	101.5	118.5	134	139	133	118.5	100	108	102.5	71.5	98.5	95.5	60
43R221	Herstal	150	127.5	146.5	195	155	203.5	NA	128.5	111	122	66.5	115.5	101.5	59
43R222	Liège (ISSeP)	NA	NA	NA	NA	154.5	121.5	NA	NA	NA	NA	NA	NA	NA	NA
43R240	Engis	129	163.5	149.5	200.5	175	208.5	123.5	115	99	110.5	63	112	96.5	52.5
43R401	Namur	120	140.5	125.5	194	157.5	189.5	109	112	100	100	63.5	108.5	99	57.5
45R502	Lodelinsart	115	108	128	201	157.5	209	98	97.5	NA	NA	NA	NA	NA	NA

Interpolated spatial average in :
Brussels	120	114	136	182	156	169	101	102	76	91	65	96	90	53
Flanders	128	129	156	190	161	159	102	100	83	96	73	97	95	59
Wallonia	124	108	124	164	139	156	110	101	100	101	67	104	95	60
Belgium	126	118	139	176	149	158	106	101	92	99	70	101	95	59

% of the population exposed to O₃ concentrations > 180 μg/m³ in:
Brussels	0%	0%	0%	67%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
Flanders	0%	0%	5%	92%	12%	29%	0%	0%	0%	0%	0%	0%	0%	0%
Wallonia	0%	0%	0%	57%	<1%	48%	0%	0%	0%	0%	0%	0%	0%	0%
Belgium	0%	0%	3%	78%	7%	33%	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