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Pollutant Concentrations

Readings on 17 Jul 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 11(7) 27(27) 41(-) 17(7) 0.5(5) 14(53)
South 11(7) 27(27) 33(-) 19(8) 0.4(4) 15(54)
East 14(9) 19(19) 32(-) 17(7) 1.1(11) 12(51)
West 35(22) 28(28) 30(-) 20(9) 0.3(3) 16(55)
Central 10(6) 22(22) 42(-) 20(8) 0.9(9) 11(45)

1-hr PM2.5 (µg/m3)b Readings on 16 Jul 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 13 10 15 11 6 13 9 16 15 17 19 21
South 17 14 9 6 8 8 11 17 12 28 18 13
East 17 10 14 6 5 11 12 14 13 14 19 11
West 12 16 14 12 8 16 13 15 17 20 17 20
Central 17 17 8 8 9 5 8 16 12 12 15 19
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 20 17 12 7 15 10 11 15 10 19 16 13
South 15 11 12 29 7 25 8 7 13 19 21 21
East 12 15 7 13 12 13 11 18 14 18 10 11
West 23 22 21 16 18 20 5 7 18 11 13 22
Central 11 12 13 8 13 3 12 5 10 4 10 14

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 16 Jul 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 55 54 53 47 38 37 39 51 52 55 56 57
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 56 56 54 54 53 53 51 47 45 52 53 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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