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Pollutant Concentrations

Readings on 14 May 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 8(5) 29(29) 29(-) 11(5) 0.5(5) 16(56)
South 16(10) 20(20) 13(-) 16(7) 0.4(4) 12(51)
East 12(8) 17(17) 14(-) 29(12) 0.6(6) 12(50)
West 20(12) 32(32) 28(-) 18(7) 0.6(6) 18(57)
Central 10(6) 19(19) 22(-) 18(8) 0.5(5) 11(46)

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

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 11 14 8 12 12 17 22 25 31 20 23 16
South 11 9 7 6 7 7 10 15 15 12 7 10
East 11 9 8 13 14 13 18 15 17 17 15 9
West 13 16 24 28 23 24 9 21 22 23 28 7
Central 9 7 10 5 12 13 8 17 16 9 8 11
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 15 10 30 23 14 9 16 16 17 20 9 8
South 11 15 22 8 18 11 15 17 19 11 12 15
East 9 8 18 12 13 17 7 12 11 6 9 8
West 24 19 18 11 17 17 15 14 19 16 9 4
Central 14 14 15 10 11 17 17 14 11 9 6 4

Note:
a Sub-index for nitrogen dioxide is reported only when the 1-hr concentration equals or exceeds 1130 µg/m3.

b There is no sub-index for 1-hr PM2.5.

3-hr PSI Readings from 1am to 12am on 13 May 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 47 46 46 48 51 53 53 55 57 58 57 53
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 53 52 56 55 55 53 54 54 54 53 51 41



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.