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Pollutant Concentrations

Readings on 24 Aug 2015

View reading for:

Region 24-hr Sulphur dioxide
(µg/m3)
24-hr PM10
(µg/m3)
1-hr Nitrogen dioxide
(µg/m3)a
8-hr Ozone
(µg/m3)
8-hr Carbon monoxide
(mg/m3)
24-hr PM2.5
(µg/m3)
North 4(2) 46(46) 30(-) 58(25) 0.4(4) 34(76)
South 11(7) 46(46) 16(-) 54(23) 0.5(5) 32(73)
East 13(8) 39(39) 8(-) 55(23) 0.4(4) 30(71)
West 24(15) 50(50) 18(-) 58(25) 0.5(5) 35(76)
Central 5(3) 43(43) 13(-) 66(28) 0.3(3) 28(69)

1-hr PM2.5 (µg/m3)b Readings on 23 Aug 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 32 30 32 28 27 26 17 21 19 20 24 33
South 30 36 29 30 26 20 25 23 22 28 27 28
East 26 27 29 24 25 22 21 17 24 21 28 32
West 30 26 28 30 29 21 24 23 26 26 34 35
Central 34 26 28 24 21 22 14 23 22 21 22 31
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 42 62 62 67 63 48 39 30 20 21 24 33
South 39 42 65 46 38 44 40 26 16 24 30 34
East 40 52 45 39 36 32 32 26 26 29 31 26
West 48 46 62 62 44 45 43 31 34 24 28 29
Central 38 46 49 45 35 35 28 23 16 25 23 25

Note:
a Sub-index for nitrogen dioxide is reported only when the 1-hour concentration exceeds 1130 µg/m3.
b There is no sub-index for 1-h PM2.5.

3-hr PSI Readings from 1am to 12am on 23 Aug 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 77 72 71 70 68 66 63 61 61 63 65 68
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 75 84 93 97 94 88 83 77 70 65 65 68



The real-time data is automatically published as soon as it is generated by our air monitoring stations. The data is subject to verification and correction subsequently if necessary.

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