Air purifier?

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WussRedXLi

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Just to add on previous data pouints

157726942.3nbLo5RD.jpg



50 ug/m3 = PSI 90 / AQI 137
52 ug/m3 = PSI 96 / AQI 142
55 ug/m3 = PSI 99 / AQI 149
57 ug/m3 = PSI 103 / AQI 152
59 ug/m3 = PSI 104 / AQI 153
61 ug/m3 = PSI 107 / AQI 154
63 ug/m3 = PSI 109 / AQI 155
65 ug/m3 = PSI 111 / AQI 156
67 ug/m3 = PSI 113 / AQI 157
70 ug/m3 = PSI 116 / AQI 158
72 ug/m3 = PSI 118 / AQI 160
75 ug/m3 = PSI 122 / AQI 161
77ug/m3 = PSI 123 / AQI 162
78 ug/m3 = PSI 124/ AQI 163

So in future, can do some pretty accurate guesstimation for PSI already if you take the 1-hr PM2.5 concentration figure from NEA.
 
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tmkedmw

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Just to add on previous data pouints

157726942.3nbLo5RD.jpg



50 ug/m3 = PSI 90
52 ug/m3 = PSI 96
55 ug/m3 = PSI 99
59 ug/m3 = PSI 104
61 ug/m3 = PSI 107
63 ug/m3 = PSI 109
65 ug/m3 = PSI 111
67 ug/m3 = PSI 113
70 ug/m3 = PSI 116
72 ug/m3 = PSI 118
75 ug/m3 = PSI 122
77ug/m3 = PSI 123
78 ug/m3 = PSI 124/125

So in future, can do some pretty accurate guesstimation for PSI already if you take the 1-hr PM2.5 concentration figure from NEA.

Wah, have enough data point to put in a lookup table which can then be used to autotranslate from psi to ug/m3 and vice versa. Anyone listening ;)
 

WussRedXLi

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Wah, have enough data point to put in a lookup table which can then be used to autotranslate from psi to ug/m3 and vice versa. Anyone listening ;)

Only for light to moderately light haze. 78 ug/m3 is not a lot.
50 ug/m3 PSI 90 is a good starting point.

I want points to at least PSI 150. :)

PS. I have added AQI figures beside the PSI figures. It's interesting, above 55 ug/m3 region, the PSI jumps faster than the AQI actually.

Ok I have found how NEA calculates PSI actually. However, buay gum coz it is PM10.
http://www.nea.gov.sg/cms/psi/computation of psi.pdf
 

WussRedXLi

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57 ug/m3 = PSI 103
78 ug/m3 = PSI 124

78 - 57 = 21, 124-103 = 21.


75 ug/m3 = PSI 122
61 ug/m3 = PSI 107

75 - 61 = 14, 122 - 107 = 13


77ug/m3 = PSI 123
65 ug/m3 = PSI 111

77 - 65 = 12, 123-111 = 12



Quite linear leh.... I am not sure where is the "breakpoint", but here goes though it could be wrong.
I can calculate via extrapolation? (not from NEA)
75 ug/m3 = PSI 122 (NEA value)
80 ug/m3 = PSI 127 (calculated)
85 ug/m3 PSI 132
90 ug/m3 = PSI 137
95 ug/m3 = PSI 142
100 ug/m3 = PSI 147
110 ug/m3 = PSI 157
120 ug/m3 = PSI 167
130 ug/m3 = PSI 177
131 ug/m3 = PSI 178? :D <- yesterday's peak was at 131 ug/m3
 

WussRedXLi

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So, furthering this...

131 ug/m3 = PSI 178 = AQI 190 (AQI 190 is calculated via the airnow.gov calculator webpage)
140 ug/m3 = PSI 187 = AQI 195
151 ug/m3 = PSI 198 = AQI 201. (AQI 201 is calculated via 151 ug/m3 into the online web calculator)

Now, 151 ug/m3 and AQI 201 is categorised as Very Unhealthy. PSI 200 is also categorised as Very Unhealthy. Ok, so I am off by 2 PSI points.

I think what I have typed is very close and legit.


131 ug/m3 = PSI 178
 

WussRedXLi

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Went to Muar and Malacca.

The numbers are PM10 actually. So it would be maybe 30% lower than our PSI.

Nota / Note
* = Habuk Halus (PM10) c = Ozon (O3)
a = Sulfur Dioksida (SO2) d = Karbon Monoksida (CO)
b = Nitrogen Dioksida (NO2) & = Lebih daripada satu pencemar


Department Of Environment, Air pollutant index

suma_image-(2)-png_7oct.png


157728231.SlU4qvib.MY1.jpg
.
 
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WussRedXLi

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Haze from Indonesia may be a problem for Singapore, Malaysia till at least mid-October

image5-61014e.jpg


INDONESIA is expecting a delay in the start of the rainy season, which means the hazy weather in Singapore and Malaysia may last till at least the middle of the month, depending on wind conditions.

The rainy season, originally expected in early October in Riau province, will now start in the middle of the month at the soonest, due to the el-Nino phenomenon, said Mr Bibin Julianto, a weather forecaster at the meteorological, climatological and geophysical office in Pekanbaru.

Jambi province in South Sumatra, another hotspot area, may see rainy season start three to four weeks late, said state weather forecaster Nurangesti, who goes by only one name

Whether Singapore and Malaysia will experience a prolonged period of hazy weather will depend on the wind directions.

In the next two to three days, the westerly winds (from west to east) and the south-easterly winds (from south-east to north-west) will be predominant above Riau, Mr Bibin told The Straits Times.

"The westerly winds are going in the Singapore direction," he said, but added that this is a transition period where the wind direction could change.

Haze from forest and plantation fire in Jambi and Riau is being blown to this region, as Indonesia is focusing fire fighting efforts in the southern part of Sumatra, where most of the fires have been detected in the past weeks.

"The number of hotspots is actually declining now, but the haze from the previous episodes (of forest and plantation fires) was stuck in the air because there was not enough rain, and is now being blown to Singapore," said Mr Agus Wibowo, head of data at the national disaster mitigation agency (BNPB), which coordinates national fire fighting efforts.

BNPB is doing cloud-seeding and water bombing operations in South Sumatra, the centre of the firefighting operations for Sumatra. A military hercules and several helicopters have been stationed there to help with the operations, said Mr Agus.

Riau has had rainfalls and is seeing PSI falling to below 50 on Tuesday, according to Mr Bibin, while Jambi's PSI is below 100. PSI levels above 100 is considered unhealthy, and between 51 and 100 are deemed moderate.

On Tuesday morning, there are 10 hotspots detected in Sumatra by the MODIS satellite - four in South Sumatra, four in Riau, one in Jambi and one in North Sumatra.

"A small number, but more could have been undetected by the satellite due to the thick haze. A lot of the haze above Riau came from South Sumatra," Mr Agus said.

In Palangkaraya, Central Kalimantan, the local authority continued to shut schools until Thursday due to the thickening haze, Kompas daily reported. Schools have been closed since last week when the PSI reached very unhealthy levels.

Almost all 10 flights leaving and going to Palangkaraya were cancelled on Monday as visibility level fell to as low as 200 metres.
 

kerwen

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this thread is very long to search, can anyone recommend a air ioniser?
 

WussRedXLi

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U mean convert into "1-hr PSI"? Why up to PSI 200 only?

Coz that's the breakpoint. Actually 50-100 is another breakpoint. All these apply differently in the equation.

If you can apply those breakpoints, then ok.
 

chuanz

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Coz that's the breakpoint. Actually 50-100 is another breakpoint. All these apply differently in the equation.

If you can apply those breakpoints, then ok.

Yea, it's a piece-wise linear function.. gosh, haven't said such a technical math term since graduated... lol
 

Asakura

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sorry there is no spoon here. and like WRX said, here don't recommend air ionisers.
 
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