
There’s been some controversy recently regarding the Air Pollutant Index (API) readings in Malaysia, with some even accusing the government of intentionally downplaying the readings.
I intended to find out exactly how the readings were different, and as a glorified techie come wannabe programmer I decide to use a data approach to this as opposed to a theoretical one. In case you’re wondering what the theoretical differences are, check out this cool article from cilisos, otherwise keep on reading.
At the crux of this issue, we first have to appreciate how API or PSI readings are calculated. Both take measurements of pollutants in the air, but only take the highest concentrated pollutant to give you the reading value. It’s hard trying to consolidate something as complex as air quality into a single number, and as a result a certain amount of ‘simplification’ is required.
Theoretically, PM2.5 measures particulate matter up to 2.5 micrometers in diameter, while PM10 measures particulate matter of up to 10 micrometers in diameter, the Singaporean Government claims that PM2.5 is the main pollutant of concern during periods of smoke haze, and hence you’d expect PM2.5 readings to be higher than Pm10.
But that’s theoretically, what about empirically?