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The thread author appears to have mistaken the acceptable NO2 level for 5.3ppb when it’s actually 53ppb. The averages on his chart never met or exceeded that va
by heartbreak 5y ago
The thread author appears to have mistaken the acceptable NO2 level for 5.3ppb when it’s actually 53ppb. The averages on his chart never met or exceeded that value.
- dahfizz 5y agoSource? The closest I could find is [1], which says 10 μg/m3 annual mean and 25 μg/m3 24-hour mean. It is for outdoor levels, but I can't imagine why the same chemical would be safer to breathe depending on whether you are inside or not as you breathe it. [1] https://www.who.int/news-room/fact-sheets/detail/ambient-(outdoor)-air-quality-and-health https://www.who.int/news-room/fact-sheets/detail/ambient-(ou...
- BugsJustFindMe 5y agoThe EPA current standard is 53ppb, but actually the WHO in September set their recommended AQG target at 10 micrograms per cubic meter with 3 step-down interim targets of 40,30,20. 10 micrograms per cubic meter of NO2 is 5.3ppb. (conversion factor is 1.88ugm3/1ppb) You can read it here: https://apps.who.int/iris/handle/10665/345329 https://apps.who.int/iris/handle/10665/345329
- heartbreak 5y agoIs the WHO value for indoor air quality? Why would WHO and EPA deviate by an order of magnitude?
- BugsJustFindMe 5y agoThe EPA value is a limit for today. The WHO value is a recommendation for the future target after some industry accommodation period. Essentially "what it is" vs "what it should be".