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Pollutant Concentrations

Air quality readings will be available hourly from 1am to 12am.

Readings on 04 Oct 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 13(8) 49(49) 34(-) 53(22) 0.5(5) 30(71)
South 12(8) 48(48) 26(-) 45(19) 0.5(5) 33(75)
East 18(11) 38(38) 19(-) 53(22) 0.3(3) 30(71)
West 36(23) 48(48) 28(-) 40(17) 0.4(4) 34(76)
Central 21(13) 43(43) 36(-) 66(28) 0.5(5) 28(69)

1-hr PM2.5 (µg/m3)b Readings on 03 Oct 2014

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 30 33 32 24 21 19 21 22 23 27 30 37
South 25 23 26 22 24 23 23 25 29 35 48 52
East 24 21 23 23 25 26 25 20 27 26 35 30
West 22 23 25 26 24 22 23 30 32 36 46 43
Central 25 23 22 20 19 22 19 23 21 23 26 35
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 37 42 43 40 43 33 33 34 30 22 23 22
South 53 54 49 49 55 38 37 27 23 17 10 25
East 36 35 44 56 28 40 40 36 29 26 21 26
West 50 52 47 48 46 48 41 36 30 26 27 18
Central 35 39 37 42 40 40 37 36 26 23 19 19

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 03 Oct 2014

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 67 66 66 65 64 63 63 63 65 67 72 77
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 82 85 87 88 88 86 83 79 75 69 64 62

Hourly updates of 3-hr PSI readings are provided from 1am to 12am. The 3-hr PSI readings are calculated based on PM2.5 concentrations only.