Air Quality
Excellent
No health implications.
15
PM2.5
29
PM10
15
O3
0.3
CO
16
SO2
22
NO2
No health implications.
Advise
Everyone can continue their outdoor activities normally.
Air Quality
Today
18 May
34
Excellent
Mon
19 May
36
Excellent
Tue
20 May
34
Excellent
Wed
21 May
41
Excellent
Thu
22 May
47
Excellent
Fri
23 May
40
Excellent
Sat
24 May
33
Excellent
Air quality in the last 12 months (Cheung Chau)
|
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
|
|||
|
2025/01
|
93
|
93
|
82
|
89
|
106
|
105
|
94
|
85
|
85
|
53
|
58
|
75
|
74
|
90
|
76
|
87
|
88
|
83
|
108
|
114
|
94
|
88
|
76
|
54
|
48
|
29
|
48
|
50
|
116
|
67
|
47
|
|
2024/12
|
79
|
85
|
80
|
74
|
80
|
75
|
46
|
37
|
55
|
61
|
52
|
39
|
49
|
59
|
58
|
71
|
77
|
65
|
61
|
72
|
80
|
78
|
90
|
81
|
81
|
80
|
86
|
83
|
83
|
85
|
99
|
|
2024/11
|
57
|
60
|
63
|
59
|
66
|
67
|
57
|
68
|
69
|
63
|
70
|
67
|
70
|
57
|
43
|
53
|
50
|
34
|
29
|
30
|
36
|
38
|
41
|
48
|
45
|
37
|
50
|
59
|
65
|
72
|
|
|
2024/10
|
41
|
38
|
53
|
54
|
54
|
58
|
62
|
54
|
46
|
49
|
60
|
64
|
71
|
70
|
52
|
42
|
49
|
50
|
37
|
33
|
47
|
49
|
31
|
48
|
56
|
52
|
37
|
30
|
36
|
49
|
62
|
|
2024/09
|
39
|
51
|
37
|
42
|
44
|
33
|
19
|
21
|
36
|
28
|
41
|
49
|
51
|
48
|
38
|
46
|
40
|
38
|
51
|
46
|
47
|
23
|
32
|
33
|
33
|
56
|
63
|
62
|
60
|
65
|
|
|
2024/08
|
29
|
34
|
39
|
52
|
45
|
51
|
53
|
51
|
53
|
42
|
42
|
28
|
22
|
33
|
23
|
27
|
22
|
21
|
35
|
38
|
29
|
25
|
31
|
43
|
42
|
45
|
45
|
53
|
44
|
38
|
47
|
|
2024/07
|
24
|
24
|
20
|
21
|
22
|
26
|
26
|
27
|
27
|
31
|
30
|
28
|
31
|
34
|
38
|
35
|
33
|
23
|
27
|
40
|
35
|
34
|
28
|
41
|
32
|
45
|
33
|
15
|
20
|
19
|
21
|
|
2024/06
|
19
|
29
|
28
|
24
|
20
|
18
|
24
|
28
|
32
|
28
|
22
|
32
|
40
|
32
|
25
|
22
|
23
|
26
|
24
|
27
|
21
|
20
|
20
|
15
|
16
|
22
|
24
|
28
|
23
|
26
|
|
|
2024/05
|
19
|
22
|
32
|
36
|
25
|
34
|
34
|
39
|
38
|
53
|
44
|
32
|
48
|
60
|
61
|
64
|
57
|
46
|
23
|
19
|
19
|
32
|
41
|
35
|
30
|
27
|
26
|
24
|
32
|
41
|
28
|
|
2024/04
|
58
|
48
|
36
|
38
|
19
|
19
|
20
|
29
|
41
|
45
|
46
|
63
|
56
|
47
|
51
|
53
|
57
|
39
|
44
|
27
|
19
|
29
|
27
|
35
|
41
|
33
|
41
|
34
|
39
|
32
|
|
|
2024/03
|
42
|
46
|
42
|
37
|
51
|
45
|
53
|
50
|
49
|
21
|
24
|
38
|
52
|
22
|
33
|
41
|
56
|
53
|
27
|
60
|
70
|
50
|
49
|
51
|
52
|
41
|
59
|
52
|
62
|
57
|
79
|
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
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