Home   Haze Updates   Pollutant Concentrations

Pollutant Concentrations

Readings on 29 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 4(2) 30(30) 29(-) 10(4) 0.3(3) 17(57)
South 9(6) 20(20) 7(-) 15(6) 0.4(4) 11(47)
East 12(7) 16(16) 10(-) 25(11) 0.5(5) 10(43)
West 34(21) 25(25) 26(-) 11(4) 0.3(3) 14(53)
Central 9(6) 19(19) 25(-) 17(7) 0.3(3) 11(46)

1-hr PM2.5 (µg/m3)b Readings on 28 May 2015

View reading for:

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
North 14 23 23 33 20 22 18 19 24 23 25 12
South 4 6 6 6 4 8 18 15 14 25 23 30
East 7 8 8 5 8 17 19 21 23 21 13 7
West 5 8 8 14 22 28 24 18 18 21 25 12
Central 6 9 9 7 9 12 22 20 23 29 11 10
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
North 23 23 25 28 14 12 9 9 8 6 4 3
South 8 14 8 15 10 10 10 12 7 7 4 7
East 7 6 12 7 8 9 13 6 4 6 4 6
West 24 22 25 12 15 10 3 3 5 6 6 3
Central 12 8 12 7 11 9 8 10 4 4 6 3

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 28 May 2015

Time 1am 2am 3am 4am 5am 6am 7am 8am 9am 10am 11am 12pm
3-hr PSI 26 34 40 48 51 54 56 58 60 61 61 59
Time 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
3-hr PSI 56 54 55 55 53 49 41 37 31 27 23 21



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.