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  2. Air quality guideline - Wikipedia

    en.wikipedia.org/wiki/Air_quality_guideline

    In terms of health effects, the guideline states that PM2.5 concentration of 10 is the lowest level at which total, cardiopulmonary and lung cancer mortality have been shown to increase with more than 95% confidence in response to long-term exposure to PM2.5. [2]

  3. Air quality index - Wikipedia

    en.wikipedia.org/wiki/Air_quality_index

    The AQI level is based on the level of six atmospheric pollutants, namely sulfur dioxide (SO 2), nitrogen dioxide (NO 2), suspended particulates smaller than 10 μm in aerodynamic diameter (PM 10), [19] suspended particulates smaller than 2.5 μm in aerodynamic diameter (PM 2.5), [19] carbon monoxide (CO), and ozone (O 3) measured at the ...

  4. How to understand the Air Quality Index - AOL

    www.aol.com/news/how-to-understand-the-air...

    The AQI measures air quality based on five major pollutants that the Clean Air Act regulates: ozone, particle pollution (AKA particulate matter or PM2.5), carbon monoxide, nitrogen dioxide and ...

  5. Clean Air Act (United States) - Wikipedia

    en.wikipedia.org/wiki/Clean_Air_Act_(United_States)

    The National Ambient Air Quality Standards (NAAQS) govern how much ground-level ozone (O 3), carbon monoxide (CO), particulate matter (PM 10, PM 2.5), lead (Pb), sulfur dioxide (SO 2), and nitrogen dioxide (NO 2) are allowed in the outdoor air. [6] The NAAQS set the acceptable levels of certain air pollutants in the ambient air in the United ...

  6. The Best Ways to Protect Yourself From Wildfire Smoke - AOL

    www.aol.com/lifestyle/best-ways-protect-yourself...

    “What we’re really worried about is the PM2.5 levels,” or the fine particles in wildfire smoke, which have a diameter of less than 2.5 micrometers. ... it’s generally OK to proceed with ...

  7. Particulate pollution - Wikipedia

    en.wikipedia.org/wiki/Particulate_pollution

    Particulate matter (PM), particularly PM2.5, was found to be harmful to aquatic invertebrates. [41] These aquatic invertebrates include fish, crustaceans, and Mollusca. In a study by Han et al, the effects of PM<2.5 micrometers on life history traits and oxidative stress were observed in Tigriopus japonicus.

  8. National Ambient Air Quality Standards - Wikipedia

    en.wikipedia.org/wiki/National_Ambient_Air...

    0.5 ppm (1,300 μg/m 3) 3-hour Not to be exceeded more than once per year 40 CFR 50.5: Particulate matter (PM 10) Primary and Secondary 150 μg/m 3: 24-hour Not to be exceeded more than once per year on average over 3 years 40 CFR 50.6: Fine particulate matter (PM 2.5) Primary 9.0 μg/m 3 (12 μg/m 3 prior to May 6, 2024) [25] annual

  9. Particulates - Wikipedia

    en.wikipedia.org/wiki/Particulates

    On the other hand, Omaha, Nebraska is performing the best and has a decrease of −1.1 μg/m 3 in PM 2.5 levels. The cleanest city in this report is Zürich, Switzerland with PM 2.5 levels of just 0.5 μg/m 3, placed first in both 2019 and 2022. The second cleanest city is Perth, with 1.7 μg/m 3 and PM 2.5 levels dropping by −6.2 μg/m 3 since