Home   Haze Updates   Pollutant Concentrations

Pollutant Concentrations

Readings on 12 May 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 3(2) 23(23) 27(-) 17(7) 0.4(4) 12(51)
South 8(5) 19(19) 14(-) 10(4) 0.3(3) 10(41)
East 10(6) 17(17) 13(-) 22(9) 0.5(5) 10(40)
West 13(8) 27(27) 27(-) 26(11) 0.5(5) 13(52)
Central 5(3) 18(18) 16(-) 14(6) 0.4(4) 9(36)

1-hr PM2.5 (µg/m3)b Readings on 11 May 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 25 19 14 5 6 10 9 10 11 10 13 13
South 13 13 10 4 11 11 6 12 11 6 8 6
East 15 18 11 8 8 11 8 11 9 11 10 7
West 16 14 26 19 8 9 6 17 14 14 15 16
Central 14 7 9 9 7 5 7 8 11 7 6 8
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 10 11 11 15 15 15 16 13 16 12 5 9
South 5 8 11 13 8 9 12 12 8 14 15 12
East 7 11 8 9 13 11 7 4 11 9 5 8
West 16 20 11 19 11 19 10 7 6 6 12 9
Central 6 9 12 9 15 15 11 5 6 4 6 12

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 11 May 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 55 55 54 51 43 37 34 39 41 45 44 42
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 41 43 43 49 50 52 52 47 40 37 37 38



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.