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Ozone Monitor
An ozone monitor is electronic equipment that monitors for ozone concentrations in the air. The instrument may be used to monitor ozone values for industrial applications or to determine the amount of ambient ozone at ground level and determine whether these values violate National Ambient Air Quality Standards (NAAQS). The ozone molecule absorbs ultraviolet radiation, and most ozone monitors utilized in regulatory applications use ultraviolet absorption to accurately quantify ozone levels. An ozone monitor of this type operates by pulling an air sample from the atmosphere into the machine with an air pump. During one cycle, the ozone monitor will take one air sample through the air inlet, and scrub the ozone from the air; for the next cycle, an air sample bypasses the scrubber and the ozone value calculated. The solenoid valve is electronically activated to shift the air flow either through the scrubber or to bypass it on a timed sequence. The difference between the two sampled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozone
Ozone (), or trioxygen, is an inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the lower atmosphere to (dioxygen). Ozone is formed from dioxygen by the action of ultraviolet (UV) light and electrical discharges within the Earth's atmosphere. It is present in very low concentrations throughout the latter, with its highest concentration high in the ozone layer of the stratosphere, which absorbs most of the Sun's ultraviolet (UV) radiation. Ozone's odour is reminiscent of chlorine, and detectable by many people at concentrations of as little as in air. Ozone's O3 structure was determined in 1865. The molecule was later proven to have a bent structure and to be weakly diamagnetic. In standard conditions, ozone is a pale blue gas that condenses at cryogenic temperatures to a dark blue liquid and finally a violet-black soli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Ambient Air Quality Standards
The U.S. National Ambient Air Quality Standards (NAAQS, pronounced ) are limits on atmospheric concentration of six pollutants that cause smog, acid rain, and other health hazards. Established by the United States Environmental Protection Agency (EPA) under authority of the Clean Air Act (42 U.S.C. 7401 et seq.), NAAQS is applied for outdoor air throughout the country. The six criteria air pollutants (CAP), or criteria pollutants, for which limits are set in the NAAQS are ozone (O3), atmospheric particulate matter, lead, carbon monoxide (CO), sulfur oxides (SOx), and nitrogen oxides (NOx). These are typically emitted from many sources in industry, mining, transportation, electricity generation and agriculture. In many cases they are the products of the combustion of fossil fuels or industrial processes. The National Emissions Standards for Hazardous Air Pollutants cover many other chemicals, and require the maximum achievable reduction that the EPA determines is feasible. Back ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
