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Pollutant Concentrations

Readings on 16 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 7(4) 28(28) 22(-) 17(7) 0.7(7) 19(58)
South 13(8) 27(27) 19(-) 21(9) 0.5(5) 15(55)
East 12(7) 24(24) 19(-) 12(5) 1.6(16) 13(52)
West 19(12) 33(33) 27(-) 17(7) 0.4(4) 18(58)
Central 8(5) 25(25) 21(-) 25(11) 1.6(16) 13(52)

1-hr PM2.5 (µg/m3)b Readings on 15 Aug 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 17 13 12 16 14 19 11 11 10 13 24 20
South 17 19 6 15 10 10 7 6 6 6 19 11
East 11 7 13 12 14 13 11 9 10 15 17 17
West 20 13 14 8 13 10 13 15 21 20 18 19
Central 8 10 11 6 12 7 13 13 14 6 6 14
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 12 25 27 45 39 31 18 18 14 15 13 11
South 14 16 14 19 27 11 19 31 22 22 22 16
East 16 14 12 14 15 17 10 17 17 8 7 13
West 19 28 28 22 30 27 12 15 17 17 15 18
Central 9 14 13 22 19 16 12 25 13 21 14 11

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 15 Aug 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 53 52 52 49 49 50 49 46 47 48 53 54
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 55 56 57 61 63 64 60 58 57 58 52 54



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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