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Pollutant Concentrations

Air quality readings will be available hourly from 7am to 11pm. Air quality readings from 12am to 6am will be made available at 7am on the same day.

 

Readings on 20 Nov 2014

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) 19(19) 36(-) 18(8) 0.3(3) 10(42)
South 8(5) 21(21) 38(-) 15(6) 0.4(4) 11(46)
East 6(4) 18(18) 10(-) 24(10) 0.3(3) 12(49)
West 5(3) 21(21) 32(-) 27(12) 0.4(4) 10(42)
Central 7(4) 17(17) 40(-) 27(11) 0.5(5) 10(40)

1-hr PM2.5 (µg/m3)b Readings on 19 Nov 2014

View reading for:

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

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 19 Nov 2014

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 52 53 54 52 49 42 39 37 37 36 36 39
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 45 49 50 54 55 54 44 34 32 31 30 27

Hourly updates of 3-hr PSI readings are provided from 7am to 11pm. The 3-hr PSI readings from 12am to 6am will be made available at 7am on the same day. The 3-hr PSI readings are calculated based on PM2.5 concentrations only.

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