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Pollutant Concentrations

Readings on 14 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(5) 36(36) 38(-) 21(9) 0.3(3) 21(61)
South 32(20) 28(28) 29(-) 20(9) 0.5(5) 17(57)
East 18(11) 23(23) 24(-) 15(6) 0.4(4) 17(56)
West 28(17) 39(39) 41(-) 16(7) 0.4(4) 23(63)
Central 14(9) 27(27) 42(-) 18(8) 0.6(6) 16(55)

1-hr PM2.5 (µg/m3)b Readings on 13 Aug 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 15 25 20 22 27 32 27 28 16 23 34 27
South 14 16 18 26 23 29 24 17 23 19 24 17
East 13 18 16 23 23 22 28 28 27 20 24 14
West 27 27 24 23 27 30 28 37 30 35 29 28
Central 20 18 15 15 20 24 25 22 29 22 12 23
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 27 25 26 18 18 14 13 10 8 15 16 21
South 18 20 19 12 12 14 14 8 13 7 6 16
East 15 17 16 9 19 6 15 9 9 8 13 9
West 27 27 29 23 21 17 10 9 6 10 9 15
Central 14 18 21 8 7 9 11 6 11 10 8 7

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 13 Aug 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 55 57 59 60 62 65 67 67 66 66 65 64
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 62 61 61 59 57 53 52 46 42 39 42 47



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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