There are some good answers here Richard Muller and Sandeep Chowdary. I’ll add a bit more explanation about PM 2.5 AQIs and a funny quirk about how they are calculated using stepwise linear functions. How is PM 2.5 AQI calculated? (Note: this is for the US AQI scale. We’ll be discussing different countries’ scales […]
Tag: WHO
So You Thought Hong Kong’s Pollution Comes from Mainland China?
Air pollution is a serious problem in Hong Kong, and Hong Kongers often complain that the worst of it comes from Mainland China. Is that fact or a convenient scapegoat? After all, Hong Kong is a densely populated developed city with one of the busiest ports in the World – it is likely that they […]
How’s the Air in Nepal?
A user on Quora asked recently how bad the air pollution in Nepal is. Nepal has glorious mountains and shining temples. But how is the air? I checked the World Health Organization’s global PM2.5 database. According to that database, Kathmandu’s PM2.5 particulate pollution averaged 49 micrograms/m3 in 2013: That’s just about double the […]