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Pollutant Concentrations

Readings on 19 Sep 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 6(3) 70(60) 28(-) 45(19) 0.9(9) 52(97)
South 10(6) 66(58) 20(-) 37(16) 0.9(9) 48(92)
East 14(9) 61(56) 26(-) 33(14) 0.7(7) 46(89)
West 14(9) 73(62) 7(-) 40(17) 1(10) 54(99)
Central 7(4) 63(57) 36(-) 46(20) 0.9(9) 42(85)

1-hr PM2.5 (µg/m3)b Readings on 18 Sep 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 41 32 35 31 37 32 25 17 18 24 29 34
South 35 34 33 37 31 27 25 16 25 20 21 25
East 35 30 31 32 39 24 19 29 23 24 18 19
West 41 34 35 30 22 23 17 29 28 30 36 40
Central 32 28 30 21 31 23 13 20 21 16 21 23
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 53 51 50 78 89 87 75 80 63 51 105 120
South 32 42 48 71 69 69 89 69 79 74 99 89
East 36 39 43 55 43 77 75 78 74 76 90 91
West 42 54 66 85 117 97 87 87 87 70 62 85
Central 38 33 52 63 72 86 67 63 56 54 66 72

Note:
a Sub-index for nitrogen dioxide is reported only when the 1-hour concentration exceeds 1130 µg/m3.
b There is no sub-index for 1-h PM2.5.

3-hr PSI Readings from 1am to 12am on 18 Sep 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 81 78 75 73 73 70 66 63 62 63 64 66
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 73 80 89 100 113 124 127 126 122 117 120 127



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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