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Pollutant Concentrations

Readings on 15 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(4) 133(92) 47(-) 29(12) 1.6(16) 92(139)
South 10(6) 121(86) 34(-) 25(11) 1.6(16) 96(143)
East 10(6) 93(72) 6(-) 44(19) 1.9(19) 78(124)
West 33(21) 133(91) 18(-) 32(14) 1.5(15) 107(155)
Central 9(5) 108(79) 39(-) 37(15) 1.5(15) 79(126)

1-hr PM2.5 (µg/m3)b Readings on 14 Sep 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 143 134 123 103 54 30 32 23 25 27 45 41
South 176 146 124 61 28 26 30 25 28 28 37 55
East 182 101 65 39 25 22 25 26 20 29 44 51
West 204 155 129 88 68 29 21 23 33 32 71 84
Central 158 122 105 51 27 20 14 20 22 22 33 52
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 61 79 93 106 112 104 97 181 238 158 109 87
South 58 62 83 97 113 121 187 341 161 119 106 87
East 49 67 55 61 101 96 132 295 142 93 80 63
West 81 94 110 126 119 90 195 279 223 154 87 86
Central 53 62 76 92 107 95 112 260 150 88 81 83

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 14 Sep 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 222 210 187 151 119 88 71 65 65 66 75 86
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 99 109 118 131 144 150 167 223 249 242 181 146



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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