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Pollutant Concentrations

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

Readings on 09 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 20(12) 59(55) 38(-) 46(19) 0.7(7) 38(80)
South 11(7) 56(53) 28(-) 32(14) 0.7(7) 42(85)
East 10(6) 47(47) 13(-) 51(22) 0.5(5) 38(81)
West 30(19) 65(58) 37(-) 38(16) 0.8(8) 48(92)
Central 19(12) 54(53) 34(-) 59(25) 0.7(7) 38(80)

1-hr PM2.5 (µg/m3)b Readings on 08 Oct 2014

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 18 29 36 37 38 32 35 39 36 23 21 30
South 26 35 34 36 42 34 28 32 24 27 44 43
East 31 38 37 40 37 34 36 36 29 24 21 27
West 33 24 27 38 39 37 46 45 34 43 38 34
Central 30 32 39 30 34 32 31 31 28 15 23 26
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 35 40 43 49 54 52 41 58 57 50 26 21
South 37 48 47 46 58 65 50 67 57 47 50 30
East 31 37 35 46 47 46 50 66 50 50 53 21
West 39 38 45 57 80 90 89 82 69 53 35 42
Central 32 35 46 44 55 54 54 59 66 40 39 37

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 08 Oct 2014

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 68 70 73 76 78 78 78 77 76 72 71 71
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 74 77 82 87 94 102 105 107 107 104 93 82

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.