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Pollutant Concentrations

Readings on 19 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 5(3) 34(34) 38(-) 31(13) 0.3(3) 17(57)
South 11(7) 35(35) 22(-) 30(13) 0.4(4) 18(58)
East 10(6) 29(29) 9(-) 40(17) 0.6(6) 19(59)
West 38(24) 40(40) 28(-) 30(13) 0.5(5) 22(62)
Central 7(4) 32(32) 23(-) 44(19) 0.2(2) 16(55)

1-hr PM2.5 (µg/m3)b Readings on 18 Aug 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 12 17 10 12 9 10 11 9 11 21 17 20
South 11 19 7 17 8 11 18 13 10 18 13 19
East 13 14 13 14 11 13 17 11 13 17 22 19
West 8 16 21 8 8 14 8 18 17 22 26 28
Central 9 9 6 8 5 10 11 11 11 17 15 17
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 31 33 34 39 37 29 16 15 10 5 5 7
South 19 28 31 32 24 24 22 28 15 16 22 15
East 24 26 29 35 25 25 27 28 20 16 13 14
West 30 38 39 38 43 28 26 9 20 22 19 18
Central 18 27 31 33 29 16 19 21 11 11 17 15

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 18 Aug 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 48 51 51 52 43 44 46 51 52 54 56 59
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 61 66 70 74 75 72 67 62 59 56 54 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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