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Pollutant Concentrations

Readings on 16 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 10(6) 21(21) 52(-) 27(11) 0.4(4) 11(48)
South 13(8) 23(23) 32(-) 19(8) 0.5(5) 14(53)
East 11(7) 18(18) 17(-) 21(9) 0.6(6) 12(48)
West 31(19) 26(26) 38(-) 24(10) 0.3(3) 13(52)
Central 7(4) 20(20) 42(-) 20(9) 0.7(7) 9(39)

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

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 7 3 5 7 9 5 9 9 9 9 15 14
South 7 3 6 9 5 7 9 12 9 14 20 13
East 6 11 8 5 8 7 7 6 11 12 10 12
West 13 3 7 3 13 5 6 10 13 17 15 16
Central 5 4 7 6 4 6 5 17 9 11 10 6
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 10 16 16 25 22 13 10 11 10 10 12 17
South 11 9 16 18 16 14 15 26 24 33 25 16
East 13 9 14 8 15 11 22 20 12 17 18 19
West 22 12 13 23 16 22 16 16 6 15 17 15
Central 11 9 11 10 14 16 12 14 7 6 15 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 Jul 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 26 27 27 24 29 27 29 33 39 47 51 52
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 52 51 52 53 55 56 55 55 54 54 54 56



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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