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Pollutant Concentrations

Readings on 23 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 4(3) 32(32) 35(-) 12(5) 0.4(4) 19(59)
South 13(8) 25(25) 6(-) 10(4) 0.5(5) 13(52)
East 11(7) 21(21) 18(-) 27(11) 0.4(4) 14(53)
West 35(22) 29(29) 32(-) 11(5) 0.3(3) 17(57)
Central 10(6) 21(21) 21(-) 21(9) 0.4(4) 12(49)

1-hr PM2.5 (µg/m3)b Readings on 22 May 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 14 13 10 21 31 34 26 21 28 26 23 16
South 15 10 9 14 11 8 14 13 24 16 23 14
East 14 9 13 10 13 12 15 13 16 17 13 16
West 12 9 19 10 18 10 14 12 19 24 27 24
Central 12 9 6 8 9 12 11 13 10 15 7 10
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 21 26 23 17 13 6 11 21 14 15 16 8
South 12 8 6 17 10 17 11 11 11 14 10 12
East 13 20 13 13 17 18 19 14 13 20 10 10
West 33 18 12 17 21 12 14 27 18 17 17 10
Central 24 16 17 13 10 17 13 13 10 11 10 8

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 22 May 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 53 51 49 48 53 54 55 54 56 58 59 58
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 58 58 57 55 54 54 53 54 54 55 53 52



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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