Air Quality
Excellent
No health implications.
12
PM2.5
27
PM10
27
O3
0.2
CO
5
SO2
4
NO2
No health implications.
Advise
Everyone can continue their outdoor activities normally.
Air Quality
Today
11 Feb
56
Good
Thu
12 Feb
63
Good
Fri
13 Feb
67
Good
Sat
14 Feb
70
Good
Sun
15 Feb
71
Good
Mon
16 Feb
65
Good
Tue
17 Feb
15
Excellent
Air quality in the last 12 months (Cheung Chau)
|
2026/01
|
50
|
34
|
39
|
56
|
43
|
42
|
51
|
57
|
58
|
68
|
61
|
63
|
73
|
75
|
78
|
82
|
80
|
78
|
75
|
55
|
33
|
33
|
35
|
56
|
65
|
68
|
47
|
53
|
60
|
52
|
30
|
|
2025/12
|
47
|
48
|
77
|
80
|
76
|
82
|
84
|
79
|
69
|
66
|
72
|
66
|
37
|
52
|
58
|
59
|
53
|
59
|
67
|
70
|
62
|
71
|
74
|
50
|
42
|
51
|
59
|
63
|
61
|
62
|
58
|
|
2025/11
|
41
|
42
|
30
|
20
|
27
|
40
|
33
|
30
|
23
|
23
|
23
|
44
|
43
|
41
|
54
|
53
|
54
|
41
|
40
|
44
|
52
|
52
|
60
|
63
|
53
|
65
|
65
|
74
|
68
|
58
|
|
|
2025/10
|
55
|
38
|
38
|
45
|
25
|
21
|
31
|
51
|
42
|
54
|
58
|
45
|
32
|
32
|
38
|
42
|
54
|
54
|
30
|
23
|
21
|
27
|
32
|
46
|
50
|
52
|
46
|
45
|
54
|
59
|
42
|
|
2025/09
|
36
|
37
|
49
|
57
|
50
|
48
|
46
|
19
|
24
|
26
|
26
|
38
|
44
|
47
|
44
|
32
|
38
|
45
|
43
|
41
|
24
|
23
|
26
|
20
|
19
|
26
|
39
|
39
|
39
|
45
|
|
|
2025/08
|
33
|
34
|
30
|
36
|
28
|
27
|
28
|
31
|
49
|
54
|
57
|
54
|
48
|
46
|
22
|
29
|
35
|
19
|
22
|
27
|
27
|
38
|
41
|
34
|
27
|
33
|
50
|
34
|
36
|
27
|
37
|
|
2025/07
|
23
|
25
|
33
|
45
|
51
|
40
|
50
|
35
|
45
|
37
|
34
|
29
|
34
|
43
|
37
|
43
|
45
|
53
|
34
|
27
|
18
|
20
|
23
|
26
|
42
|
46
|
47
|
56
|
46
|
39
|
34
|
|
2025/06
|
41
|
39
|
27
|
42
|
49
|
40
|
37
|
32
|
45
|
26
|
24
|
19
|
18
|
19
|
24
|
23
|
21
|
24
|
25
|
21
|
24
|
24
|
29
|
32
|
36
|
30
|
22
|
25
|
27
|
23
|
|
|
2025/05
|
35
|
45
|
43
|
34
|
33
|
31
|
23
|
32
|
23
|
43
|
45
|
55
|
58
|
51
|
39
|
34
|
25
|
28
|
30
|
35
|
38
|
41
|
44
|
30
|
51
|
43
|
56
|
56
|
24
|
27
|
32
|
|
2025/04
|
40
|
64
|
76
|
71
|
93
|
79
|
79
|
78
|
76
|
80
|
58
|
104
|
239
|
168
|
127
|
107
|
91
|
70
|
52
|
47
|
59
|
46
|
35
|
43
|
25
|
35
|
52
|
35
|
55
|
62
|
|
|
2025/03
|
50
|
49
|
66
|
36
|
24
|
25
|
31
|
35
|
47
|
66
|
86
|
64
|
53
|
58
|
44
|
27
|
52
|
40
|
59
|
70
|
81
|
92
|
103
|
108
|
92
|
81
|
51
|
56
|
22
|
21
|
25
|
|
2025/02
|
45
|
29
|
20
|
30
|
48
|
58
|
30
|
58
|
58
|
62
|
73
|
61
|
59
|
78
|
99
|
53
|
42
|
43
|
66
|
69
|
29
|
39
|
23
|
38
|
68
|
93
|
72
|
64
|
|||
|
1
|
2
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3
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4
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5
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6
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7
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8
|
9
|
10
|
11
|
12
|
13
|
14
|
15
|
16
|
17
|
18
|
19
|
20
|
21
|
22
|
23
|
24
|
25
|
26
|
27
|
28
|
29
|
30
|
31
|
- Excellent
- Good
- Lightly
- Moderately
- Heavily
- Severely
Air quality source: CNEMC
*: primary pollution