Is there a difference between the pollution levels at higher vs lower floors in a high rise building?

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    $\begingroup$ I remember seeing measurements performed at different floors/levels of a building in the German city of Stuttgarts shown a the Air Quality Conference 2016 in Milano. The NO_2 levels were decreasing with increasing hight. I am not sure about other air pollutants. $\endgroup$ Apr 6, 2021 at 6:39
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    $\begingroup$ I think this strongly depends on the city and weather. Findings for Delhi or Shanghai during winter months with inversion and coal/wood fires will strongly differ from NYC during windy & wet Hurricane season or Perth during windy bushfire season. $\endgroup$
    – Erik
    Apr 6, 2021 at 8:09
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    $\begingroup$ Honestly, I'd think it should cluster around 2 options: chemicals of fairly local origin (the most extreme pollutions?).. should have levels either lower or similar on upper floors... because those pollutants come concentrated near the ground source, then disperse with upwards\horizontal spread. (Fog is a decent trace of where local pollutants are when dealing with local inversions.) Whereas if we're talking about chemicals\smoke of distant origin, because the stronger wind to advect them, plus the inversions, are aloft, would think levels would usually be a bit greater at higher floors. $\endgroup$ Apr 6, 2021 at 14:58
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    $\begingroup$ So Saharan dust or distant wildfire smoke would be worse aloft, whereas the city's own cars and industrial releases probably tend to be maximum nearer the ground if anywhere, particularly right near the origin point(s). $\endgroup$ Apr 6, 2021 at 15:00
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    $\begingroup$ @Nav : Unfortunately, I did not find it. Therefore, I just posted this comment and not an answer. $\endgroup$ Apr 6, 2021 at 16:45

1 Answer 1


Yes, the higher floors will have less pollution than the street level.

The wind rises as a function of altitude, so the street will have less new air coming in, on average:

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Some of the pollutants are lighter than air, i.e. Ozone, and some are heavier, i.e. particulate matter, they tend to rise or fall very slowly, so they can be slightly different gradients at different floors of the building.

The pollutants are diffuse clouds that rely on ambient air currents for dispersion.


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