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Pollutant Concentrations

Readings on 25 Jun 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) 31(31) 36(-) 40(17) 0.5(5) 18(57)
South 9(5) 32(32) 6(-) 31(13) 0.5(5) 17(56)
East 11(7) 27(27) 9(-) 47(20) 0.7(7) 18(58)
West 41(25) 36(36) 38(-) 37(16) 0.4(4) 21(62)
Central 7(4) 31(31) 32(-) 40(17) 0.5(5) 16(55)

1-hr PM2.5 (µg/m3)b Readings on 24 Jun 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 14 9 11 14 12 18 13 17 12 18 20 18
South 17 15 13 12 11 15 9 10 17 14 23 9
East 12 12 17 10 15 14 16 9 14 18 22 20
West 22 16 15 15 18 15 18 20 15 22 27 28
Central 11 8 13 13 16 13 11 10 13 11 17 20
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 21 23 21 19 22 24 20 17 16 20 25 22
South 21 17 12 21 21 17 23 21 16 28 28 13
East 21 21 21 19 21 23 26 31 24 20 20 15
West 24 20 17 20 26 19 26 26 24 22 27 33
Central 20 22 23 21 19 20 21 17 17 14 18 10

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 24 Jun 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 55 53 53 52 53 53 54 53 53 54 57 59
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 61 60 60 60 60 61 62 62 62 61 61 61



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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