Number of days with highest 8h-mean concentration > 120 µg/m³ (EU target value)Number of days with highest hourly concentration > 180 µg/m³ (EU information threshold)Number of days with highest hourly concentration > 240 µg/m³ (EU alert threshold)

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The number of days with daily highest 8-hour mean ozone concentrations higher than 120 µg/m³ are published in the table below.

According to EC directive 2008/50/EC the target value for the protection of human health, is the daily highest 8-hour mean ozone concentration of 120 µg/m³ that cannot be exceeded more then 25 times, averaged over three calender years. The averages over three years are published in the yellow table cells. The orange table cells indicate an exceedance. The row below the averages over three years give the number of days with highest 8-hour mean concentration above 120 µg/m³ per calender year. The long-term objective for the protection of human health, is no more exceedances of the daily highest 8-hour mean of 120 µg/m³.

This table will be updated every day at around 07:00 AM.

Code City Region 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026*
41B004 Brussel (Sint-Katelijne) Bru 5 7 8 12 8 8 5 7
9 3 3 16 6 15 3 7
41B006 Brussel (EU Parlement) Bru 11
11 NA
41B011 Sint-Agatha-Berchem Bru 11 17 21 24 15 15 14 14 13
12 9 11 32 21 19 6 21 16 5 17 13
41MEU1 Neder-Over-Heembeek Bru 27 27 23 13 15 13 13 12
27 NA 19 6 19 15 6 15 11
41N043 Voorhaven (Haren) Bru 4 7 10 14 8 9 8 9 9
8 1 3 18 9 14 1 11 11 6 9 6
41R001 Sint-Jans-Molenbeek Bru 3 7 11 14 10 8 7 8 8
4 0 4 17 13 13 3 NA 11 5 9 10
41R012 Ukkel Bru 9 14 17 20 15 18 17 16 14
14 5 9 27 14 19 12 24 15 9 18 13
41WOL1 Sint-Lambrechts-Woluwe Bru 2 3 4 6 6 9
5 0 2 6 3 9
42N016 Dessel Fla 17 27 28 31 18 19 18 20 17
19 18 15 47 21 26 8 23 23 15 14 18
42N027 Bree Fla 20 27 28 29 17 18 17 19 19
22 18 21 41 22 24 6 24 20 12 25 22
42N035 Aarschot Fla 18 25 27 30 18 18 17 20 20
20 14 19 42 21 27 6 22 22 15 22 21
42N040 Sint-Pieters-Leeuw Fla 14 22 23 24 14 15 14 15 14
12 12 17 36 15 20 6 20 17 7 19 13
42N045 Hasselt Fla 19 19
19 19
42N046 Gellik Fla 17 23 25 27 16 16 15 18 17
20 15 15 39 21 22 4 23 19 13 19 19
42N047 Hasselt Fla 25 15 17 16 20 21
NA 25 4 22 22 15 26 19
42N054 Walshoutem Fla 13 20 23 26 14 14 11 17 14
14 9 17 35 18 24 0 19 14
42R801 Borgerhout Fla 2 5 7 10 3 6 9 11 13
4 0 3 13 6 NA 0 11 17 6 15 15
42R811 Schoten Fla 15 22 23 24 14 13 14 16 17
15 15 15 35 19 18 5 17 20 11 20 19
42R831 Berendrecht Fla 11 15 18 20 15 15 14 17 18
13 8 12 25 16 20 8 16 18
42R841 Mechelen (Technologielaan) Fla 11 9
12 9
44M705 Roeselare (Haven) Fla 7 12 14 15 9 9 9 12 11
6 6 10 20 13 13 0 14 14 9 11 19
44N012 Moerkerke Fla 9 12 13 13 10 11 12 13 12
6 11 10 15 13 12 6 14 16 10 9 12
44N029 Houtem (Veurne) Fla 5 8 9 11 8 8 8 8 7
5 5 4 14 9 11 4 9 11 3 8 8
44N051 Idegem Fla 10 20 22 24 17 21 18 18 16
10 7 14 39 12 22 NA 19 16
44N052 Zwevegem Fla 7 13 17 19 12 11 5
6 2 12 25 14 17 5
44R701 Gent (Baudelopark) Fla 9 14 17 20 14 12 11 15 15
8 8 11 22 18 19 4 NA 17 13 16 23
44R710 Destelbergen Fla 9 13 18 19 13 13 13 15 13
12 5 11 24 19 15 5 18 16 10 14 20
44R740 Sint-Kruiswinkel Fla 10 14 16 17 11 13 12 16 14
12 7 12 22 14 15 5 18 14
43N060 Havinnes Wal 6 11 12 16 9 8 9 10 11
7 5 5 22 10 15 2 7 18 4 12 10
43N063 Corroy-Le-Grand Wal 9 16 20 24 14 14 3
12 4 10 34 15 24 3
43N066 Eupen Wal 10 21 23 29 10 12 14 15 12
11 8 12 42 15 NA 4 20 18 8 9 14
43N070 Mons Wal 5 12 15 21 13 15 10 11 9
7 2 7 27 12 25 3 16 11 5 12 8
43N073 Vezin Wal 14 21 25 27 16 15 14 15 15
16 10 16 38 21 21 5 19 17 10 18 14
43N085 Vielsalm Wal 10 16 17 20 10 10 9 9 8
15 9 7 31 13 16 2 12 13 2 10 5
43N093 Sinsin Wal 10 15 22 26 17 14 12 12 10
16 5 9 31 25 22 3 17 16 4 11 13
43N100 Dourbes Wal 14 20 24 31 21 20 15 14 10
20 11 12 37 23 32 9 18 17 6 7 20
43N113 Saint-Ode Wal 11 21 19 22 13 13 12 12 9
14 NA 8 33 17 17 4 18 14 3 11 8
43N121 Offagne Wal 12 16 17 22 13 14 11 10 6
20 10 6 33 13 21 5 17 11 2 6 7
43N132 Habay-La-Neuve Wal 13 18 21 25 15 13 11 10 9
19 11 8 36 18 20 8 12 14 4 8 5
43R201 Liège Wal

43R221 Herstal Wal 9 17 22 23 12 11 12 13 14
11 3 13 36 18 15 3 14 18 8 17 15
43R222 Liège (ISSeP) Wal 10 18 22 24 13 12 12 13 14
12 5 12 37 16 19 3 15 17 8 18 16
43R240 Engis Wal 15 25 21 23 12 14 13 14 11
16 NA 14 35 15 19 3 20 16 6 10 9
43R401 Namur Wal 9 7 8
NA NA NA NA 9 5 9 11
45R502 Lodelinsart Wal 7 16 19 22 11 11 8 9 7
10 4 8 35 14 18 2 14 9 4 8 9

Code	City	Region	2015	2016	2017	2018	2019	2020	2021	2022	2023	2024	2025
41B004	Brussel (Sint-Katelijne)	Bru			5	7	8	12	8	8	5	7
	9	3	3	16	6	15	3	7
41B006	Brussel (EU Parlement)	Bru			11
	11	NA
41B011	Sint-Agatha-Berchem	Bru			11	17	21	24	15	15	14	14	13
	12	9	11	32	21	19	6	21	16	5	17	13
41MEU1	Neder-Over-Heembeek	Bru				27	27	23	13	15	13	13	12
				27	NA	19	6	19	15	6	15	11
41N043	Voorhaven (Haren)	Bru			4	7	10	14	8	9	8	9	9
	8	1	3	18	9	14	1	11	11	6	9	6
41R001	Sint-Jans-Molenbeek	Bru			3	7	11	14	10	8	7	8	8
	4	0	4	17	13	13	3	NA	11	5	9	10
41R012	Ukkel	Bru			9	14	17	20	15	18	17	16	14
	14	5	9	27	14	19	12	24	15	9	18	13
41WOL1	Sint-Lambrechts-Woluwe	Bru			2	3	4	6	6	9
	5	0	2	6	3	9
42N016	Dessel	Fla			17	27	28	31	18	19	18	20	17
	19	18	15	47	21	26	8	23	23	15	14	18
42N027	Bree	Fla			20	27	28	29	17	18	17	19	19
	22	18	21	41	22	24	6	24	20	12	25	22
42N035	Aarschot	Fla			18	25	27	30	18	18	17	20	20
	20	14	19	42	21	27	6	22	22	15	22	21
42N040	Sint-Pieters-Leeuw	Fla			14	22	23	24	14	15	14	15	14
	12	12	17	36	15	20	6	20	17	7	19	13
42N045	Hasselt	Fla			19	19
	19	19
42N046	Gellik	Fla			17	23	25	27	16	16	15	18	17
	20	15	15	39	21	22	4	23	19	13	19	19
42N047	Hasselt	Fla						25	15	17	16	20	21
					NA	25	4	22	22	15	26	19
42N054	Walshoutem	Fla			13	20	23	26	14	14	11	17	14
	14	9	17	35	18	24	0	19	14
42R801	Borgerhout	Fla			2	5	7	10	3	6	9	11	13
	4	0	3	13	6	NA	0	11	17	6	15	15
42R811	Schoten	Fla			15	22	23	24	14	13	14	16	17
	15	15	15	35	19	18	5	17	20	11	20	19
42R831	Berendrecht	Fla			11	15	18	20	15	15	14	17	18
	13	8	12	25	16	20	8	16	18
42R841	Mechelen (Technologielaan)	Fla			11	9
	12	9
44M705	Roeselare (Haven)	Fla			7	12	14	15	9	9	9	12	11
	6	6	10	20	13	13	0	14	14	9	11	19
44N012	Moerkerke	Fla			9	12	13	13	10	11	12	13	12
	6	11	10	15	13	12	6	14	16	10	9	12
44N029	Houtem (Veurne)	Fla			5	8	9	11	8	8	8	8	7
	5	5	4	14	9	11	4	9	11	3	8	8
44N051	Idegem	Fla			10	20	22	24	17	21	18	18	16
	10	7	14	39	12	22	NA	19	16
44N052	Zwevegem	Fla			7	13	17	19	12	11	5
	6	2	12	25	14	17	5
44R701	Gent (Baudelopark)	Fla			9	14	17	20	14	12	11	15	15
	8	8	11	22	18	19	4	NA	17	13	16	23
44R710	Destelbergen	Fla			9	13	18	19	13	13	13	15	13
	12	5	11	24	19	15	5	18	16	10	14	20
44R740	Sint-Kruiswinkel	Fla			10	14	16	17	11	13	12	16	14
	12	7	12	22	14	15	5	18	14
43N060	Havinnes	Wal			6	11	12	16	9	8	9	10	11
	7	5	5	22	10	15	2	7	18	4	12	10
43N063	Corroy-Le-Grand	Wal			9	16	20	24	14	14	3
	12	4	10	34	15	24	3
43N066	Eupen	Wal			10	21	23	29	10	12	14	15	12
	11	8	12	42	15	NA	4	20	18	8	9	14
43N070	Mons	Wal			5	12	15	21	13	15	10	11	9
	7	2	7	27	12	25	3	16	11	5	12	8
43N073	Vezin	Wal			14	21	25	27	16	15	14	15	15
	16	10	16	38	21	21	5	19	17	10	18	14
43N085	Vielsalm	Wal			10	16	17	20	10	10	9	9	8
	15	9	7	31	13	16	2	12	13	2	10	5
43N093	Sinsin	Wal			10	15	22	26	17	14	12	12	10
	16	5	9	31	25	22	3	17	16	4	11	13
43N100	Dourbes	Wal			14	20	24	31	21	20	15	14	10
	20	11	12	37	23	32	9	18	17	6	7	20
43N113	Saint-Ode	Wal			11	21	19	22	13	13	12	12	9
	14	NA	8	33	17	17	4	18	14	3	11	8
43N121	Offagne	Wal			12	16	17	22	13	14	11	10	6
	20	10	6	33	13	21	5	17	11	2	6	7
43N132	Habay-La-Neuve	Wal			13	18	21	25	15	13	11	10	9
	19	11	8	36	18	20	8	12	14	4	8	5
43R201	Liège	Wal

43R221	Herstal	Wal			9	17	22	23	12	11	12	13	14
	11	3	13	36	18	15	3	14	18	8	17	15
43R222	Liège (ISSeP)	Wal			10	18	22	24	13	12	12	13	14
	12	5	12	37	16	19	3	15	17	8	18	16
43R240	Engis	Wal			15	25	21	23	12	14	13	14	11
	16	NA	14	35	15	19	3	20	16	6	10	9
43R401	Namur	Wal									9	7	8
					NA	NA	NA	NA	9	5	9	11
45R502	Lodelinsart	Wal			7	16	19	22	11	11	8	9	7
	10	4	8	35	14	18	2	14	9	4	8	9

* Not validated data.
"NA" means that there were less then 75% available days in the summer season (april-september) with sufficient measuring data to calculate the daily highest 8-hour mean ozone concentration.