enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Air quality index - Wikipedia

    en.wikipedia.org/wiki/Air_quality_index

    An air quality index (AQI) is an indicator developed by government agencies [1] to communicate to the public how polluted the air currently is or how polluted it is forecast to become. [2][3] As air pollution levels rise, so does the AQI, along with the associated public health risk. Children, the elderly and individuals with respiratory or ...

  3. Aeronautical chart conventions (United States) - Wikipedia

    en.wikipedia.org/wiki/Aeronautical_chart...

    The charts are published "in accordance with Interagency Air Cartographic Committee specifications and agreements, approved by the Department of Defense and the Federal Aviation Administration". The legend of an aeronautical chart lists many of the symbols, colors and codes used to convey information to the map reader.

  4. USAAF unit identification aircraft markings - Wikipedia

    en.wikipedia.org/wiki/USAAF_unit_identification...

    USAAF unit identification aircraft markings. USAAF unit identification aircraft markings, commonly called "tail markings" after their most frequent location, were numbers, letters, geometric symbols, and colors painted onto the tails (vertical stabilizer fins, rudders and horizontal surfaces), wings, or fuselages of the aircraft of the United ...

  5. NowCast (air quality index) - Wikipedia

    en.wikipedia.org/wiki/NowCast_(air_quality_index)

    The PM NowCast is a weighted average of hourly air monitoring data used by the United States Environmental Protection Agency (USEPA) for real-time reporting of the Air Quality Index (AQI) for PM (PM 10 or PM 2.5). The PM NowCast is computed from the most recent 12 hours of PM monitoring data, but the NowCast weights the most recent hours of ...

  6. Badges of the United States Air Force - Wikipedia

    en.wikipedia.org/wiki/Badges_of_the_United...

    Badges earned by an Air Force officer from the 308th Rescue Squadron (2008) Air Force skill level badge symbols Badges of the United States Air Force are specific uniform insignia authorized by the United States Air Force that signify aeronautical ratings, special skills, career field qualifications, and serve as identification devices for personnel occupying certain assignments.

  7. National Ambient Air Quality Standards - Wikipedia

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

    Contents. National Ambient Air Quality Standards. The U.S. National Ambient Air Quality Standards (NAAQS, pronounced / ˈnæks / naks) are limits on atmospheric concentration of six pollutants that cause smog, acid rain, and other health hazards. [ 1 ] Established by the United States Environmental Protection Agency (EPA) under authority of the ...

  8. Ringelmann scale - Wikipedia

    en.wikipedia.org/wiki/Ringelmann_scale

    The Ringelmann scale is a scale for measuring the apparent density or opacity of smoke. [1][2] It was developed by a French professor of agricultural engineering Maximilien Ringelmann of La Station d'Essais de Machines in Paris, who first specified the scale in 1888. [3][4] The scale has 5 levels of density inferred from a grid of black lines ...

  9. Air pollution measurement - Wikipedia

    en.wikipedia.org/wiki/Air_pollution_measurement

    Air quality monitoring sensors in Port Pirie, South Australia. Air pollution measurement is the process of collecting and measuring the components of air pollution, notably gases and particulates. The earliest devices used to measure pollution include rain gauges (in studies of acid rain), Ringelmann charts for measuring smoke, and simple soot ...