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  2. Air pollution measurement - Wikipedia

    en.wikipedia.org/wiki/Air_pollution_measurement

    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 and dust collectors known as deposit gauges . [ 1 ]

  3. Beta attenuation monitoring - Wikipedia

    en.wikipedia.org/wiki/Beta_Attenuation_Monitoring

    Beta attenuation monitoring (BAM) is an air monitoring technique employing the absorption of beta radiation by solid particles extracted from air flow. The technique allows for the detection of PM 10 and PM 2.5, which are monitored by most air pollution regulatory agencies.

  4. Ohmmeter - Wikipedia

    en.wikipedia.org/wiki/Ohmmeter

    An analog ohmmeter. An ohmmeter is an electrical instrument that measures electrical resistance (the opposition offered by a circuit or component to the flow of electric current). Multimeters also function as ohmmeters when in resistance-measuring mode. An ohmmeter applies current to the circuit or component whose resistance is to be measured.

  5. Contact resistance - Wikipedia

    en.wikipedia.org/wiki/Contact_resistance

    In the semiconductor industry, Cross-Bridge Kelvin Resistor(CBKR) structures are the mostly used test structures to characterize metal-semiconductor contacts in the Planar devices of VLSI technology. During the measurement process, force the current ( I {\displaystyle I} ) between contacts 1 and 2 and measure the potential deference between ...

  6. Ringelmann scale - Wikipedia

    en.wikipedia.org/wiki/Ringelmann_scale

    Shade 1 is slightly grey and is usually categorized by air pollution boards as acceptable. It corresponds to an opacity of 20%. Shades 2, 3, 4 and 5 correspond to opacities of 40%, 60%, 80% and 100% (completely black) and are usually considered to be "black smoke" by air pollution boards of most countries.

  7. Oxygen sensor - Wikipedia

    en.wikipedia.org/wiki/Oxygen_sensor

    Applying an external voltage to the zirconia sensors, e.g. by checking them with some types of ohmmeter, may damage them. Some sensors have an air inlet to the sensor in the lead, so contamination from the lead caused by water or oil leaks can be sucked into the sensor and cause failure. [7] Symptoms of a failing oxygen sensor [8] includes:

  8. List of measuring instruments - Wikipedia

    en.wikipedia.org/wiki/List_of_measuring_instruments

    Multimeter, combines the functions of ammeter, voltmeter, and ohmmeter as a minimum. LCR meter, combines the functions of ohmmeter, capacitance meter, and inductance meter. Also called component bridge due to the bridge circuit method of measurement.

  9. Air pollutant concentrations - Wikipedia

    en.wikipedia.org/wiki/Air_pollutant_concentrations

    In other words, industrial air pollution sources located at altitudes well above sea level must comply with significantly more stringent air quality standards than sources located at sea level (since it is more difficult to comply with lower standards). For example, New Mexico's Department of the Environment has a regulation with such a ...