Haze Lai Liao Part 2/3/4/5

[Gitanic]

one of my sisters had a photo-shoot in haze for wedding.

 

actually quite romantic.

[Baal]

South earlier 300. Now 298.

[Eyke]

I remember once people said in SGP u are safe. U can go down stair to have a walk, jog at anytime of the day without worried....Not anymore with haze around

 

is SAFER! coz even the criminals will be hiding indoors in aircon

[Etnt]

I remember during the 2013 400+ period, the whole south area is shrouded in yellowish haze, right now it's still pretty whitish, though I dunno if color really matters.

 

Went from Sengkang-TPE-CTE-Rivervalley (liang court) and back the same route, basically it's a whitish blur all the way and tiring on the eyes.

 

Less cars on the road compared to a normal weekend, even for southbound CTE at ard 12pm.

 

More folks seems to be wearing mask, though quite a large proportion of those are using surgical mask rather than the n95 ones. Wonder what happened to those govt distributed ones 2 years back, all thrown away?

[Eyke]

Me follow this haze monitor :

http://by.originally.us/psi/real

 

Current reading is 299.....1 point short for MOE to close all schools tomolo.

 

u follow that, but MOE is not following that...

 

MOE is following NEA's next-day forecast for potential school-closure.

Edited September 24, 2015 by Eyke

[Lala81]

I remember during the 2013 400+ period, the whole south area is shrouded in yellowish haze, right now it's still pretty whitish, though I dunno if color really matters.

 

Went from Sengkang-TPE-CTE-Rivervalley (liang court) and back the same route, basically it's a whitish blur all the way and tiring on the eyes.

 

Less cars on the road compared to a normal weekend, even for southbound CTE at ard 12pm.

 

More folks seems to be wearing mask, though quite a large proportion of those are using surgical mask rather than the n95 ones. Wonder what happened to those govt distributed ones 2 years back, all thrown away?

 

i don't even wear n95. It's not comfortable to wear at all especially over extended periods.

 

 

u follow that, but MOE is not following that...

 

MOE is following NEA's next-day forecast for potential school-closure.

 

anyway 3hr PSI is around there also lah. 262.

[13177]

Suppose to be quite crowded outside since it is a PH and haji, but when i look out from my window, the street seems quite empty now?!

[Etnt]

 

i don't even wear n95. It's not comfortable to wear at all especially over extended periods.

 

 

anyway 3hr PSI is around there also lah. 262.

 

I'm using the 3m 9211 with the valve, pretty ok actually. Get a headache from the 3m surgical green ones without valve though, dunno if it's due to lack of air or band too tight or both.

[Ysc3]

 

I'm using the 3m 9211 with the valve, pretty ok actually. Get a headache from the 3m surgical green ones without valve though, dunno if it's due to lack of air or band too tight or both.

 

just use what hospital workers use ... those rectangular surgical masks, cheap and does the job ... those n95 masks are really an overkill !! make it more difficult to breathe also.... got many many cartons of the n95 masks at work ... no one want to use !!

 

Edited September 24, 2015 by Ysc3

[Lala81]

 

just use what hospital workers use ... those rectangular surgical masks, cheap and does the job ... those n95 masks are really an overkill !! make it more difficult to breathe also.... got many many cartons of the n95 masks at work ... no one want to use !!

 

 

err those surgical masks don't work.

[13177]

Surgical masks don't work but at least better than not wearing any mask, lol.

[13177]

Psi reading low or high, life still goes on as per normal here. Lol. That's why NEA don't really bother timely update or not.

[Happily1986]

I repeat, nobody cares about what was PSI 3 hours ago.

 

 

I think there is a lot of confusion and wrong information being passed around about how the PSI values are being generated. You guys ought to research and find out more.

 

Anyway you can always crunch out PSI using the hourly PM2.5 concentration so you can get a more a current PSI reading. It is a pretty easy job.

Edited September 24, 2015 by Happily1986

[Porker]

 

I think there is a lot of confusion and wrong information being passed around about how the PSI values are being generated. You guys ought to research and found out more.

 

Anyway you can always crunch out PSI using the hourly PM2.5 concentration so you can get a more a current PSI reading. It is a pretty easy job.

Ai chek mee siam mai Ric?

 

By the way you made a grammar mistake 😂

[Gitanic]

this is the beautiful Indonesian maid i saw just now.

[Happily1986]

Anyway for people who are interested in how the numbers are generated.

 

1.) PSI is a composite index. The sub components comprises of the raw concentration readings of sulphur dioxide (SO₂), particulate matter (PM₁₀) and fine particulate matter (PM_2.5), nitrogen dioxide (NO₂), carbon monoxide (CO) and ozone (O₃).

 

2.) PSI that is reported for the public consumption is using the 3 hourly PM 2.5 concentration

 

3.) There are mathematical functions for the individual sub components to be transform from their raw concentration readings to PSI. Alternatively you can always look up a chart to transform. Most importantly, PSI as a composite index reports the overall PSI by taking the max PSI of its sub components. It is a max function. Whichever sub component reports the highest PSI after transform, that value will be reported as the PSI reading. Not surprisingly, the max PSI reported is consistently by the PM2.5 sub component.

 

 

4.) PSI values are dimensionless but nevertheless PSI values have been classified into ranges for easy interpretation

 

5.) 3 hourly PSI values are not crunched using PM2.5 data taken 3 hours ago. if you look up the 3 hourly PSI chart/table, there are values churned out hourly. So the simple deduction is that NEA crunch out the 3 hourly PSI by averaging the PM2.5 raw data every 3 hours in a stacking manner.

 

Stacking means every hour, i derive the mean by aggregating the currently hour PM2.5 raw value and the values of the past 2 hours (3 data points) first and then perform averaging. And the next hour, i repeat so each values is being aggregated at least twice.

 

WHY NEA chose to do so? Simple.

 

Sampling noise. The finer your sampling frequency is, the more prevalent sampling noise is i.e. the fluctuations.

 

 

 

No need so complicated, I use AQI which uses the same feed from NEA and reports the hourly MAX. Average means nothing to the common man.



When TP put you on breathalyzer I'm pretty sure they won't measure your 3 hourly average.

 

Suits yourself. Kind of funny reading people writing nonsense.

Edited September 24, 2015 by Happily1986

[Lala81]

I agree the 3hr PSI is a good enough estimate of what's the air like.

 

Sudden surges in 1 hr PSI can't really be digested and effected by the people on the ground also.

 

 

Anyway for people who are interested in how the numbers are generated.

 

1.) PSI is a composite index. The sub components comprises of the raw concentration readings of sulphur dioxide (SO₂), particulate matter (PM₁₀) and fine particulate matter (PM_2.5), nitrogen dioxide (NO₂), carbon monoxide (CO) and ozone (O₃).

 

2.) PSI that is reported for the public consumption is using the 3 hourly PM 2.5 concentration

 

3.) There are mathematical functions for the individual sub components to be transform from their raw concentration readings to PSI. Alternatively you can always look up a chart to transform.

 

4.) PSI values are dimensionless but nevertheless PSI values have been classified into ranges for easy interpretation

 

5.) 3 hourly PSI values are not crunched using PM2.5 data taken 3 hours ago. if you look up the 3 hourly PSI chart/table, there are values churned out hourly. So the simple deduction is that NEA crunch out the 3 hourly PSI by averaging the PM2.5 raw data every 3 hours in a stacking manner.

 

Stacking means every hour, i derive the mean by aggregating the currently hour PM2.5 raw value and the values of the past 2 hours (3 data points) first and then perform averaging. And the next hour, i repeat so each values is being aggregated at least twice.

 

WHY NEA chose to do so? Simple.

 

Sampling noise. The finer your sampling frequency is, the more prevalent sampling noise is i.e. the fluctuations.

 

[Gitanic]

PSI is meaningless if you keep some pets.

 

For eg. your dog farted suddenly the PSI around you will go up to 3000.