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Ground-level ozone (O 3), also known as surface-level ozone and tropospheric ozone, is a trace gas in the troposphere (the lowest level of the Earth's atmosphere), with an average concentration of 20–30 parts per billion by volume (ppbv), with close to 100 ppbv in polluted areas.
In 1897 ozone gas was used as an antiseptic for the first time in a terminal cancer patient. [26] By 1900 ozone was also in use in dentistry and drinking water purification. [27] [28] In 2019 ozone was considered an effective way of killing environmental SARS (COVID19) virus.
The ozone hole was much more seen as a "hot issue" and imminent risk compared to global climate change, [13] as lay people feared a depletion of the ozone layer (ozone shield) risked increasing severe consequences such as skin cancer, cataracts, [23] damage to plants, and reduction of plankton populations in the ocean's photic zone. This was ...
These ozone generators can produce over 3 g of ozone per hour. Ozone often forms in nature under conditions where O 2 will not react. [29] Ozone used in industry is measured in μmol/mol (ppm, parts per million), nmol/mol (ppb, parts per billion), μg/m 3, mg/h (milligrams per hour) or weight percent. The regime of applied concentrations ranges ...
Following the ozone depletion in 1997 and 2011, a 90% drop in ozone was measured by weather balloons over the Arctic in March 2020, as they normally recorded 3.5 parts per million of ozone, compared to only around 0.3 parts per million lastly, due to the coldest temperatures ever recorded since 1979, and a strong polar vortex which allowed ...
However, because of the presence of Reaction 2 and 3, NO x and ozone are not in a perfectly steady state. By replacing Reaction 6 with Reaction 2 and Reaction 3, the O 3 molecule is no longer destroyed. Therefore, the concentration of ozone keeps increasing throughout the day. This mechanism can escalate the formation of ozone in smog.
A feasibility study of the ozone formed from the oxidation of nitrogen dioxide in ambient air reported by the WHO suggested that daily deaths of 1 to 2% is attributed to exposure to ozone concentration above 47.3 ppb and exposure above 75.7 ppb is attributed to 3 to 5% increase in daily mortality. A level of 114 ppb was attributed to 5 to 9% ...
A vehicle tire showing signs of ozone cracking. An antiozonant, also known as anti-ozonant, is an organic compound that prevents or retards damage caused by ozone. The most important antiozonants are those which prevent degradation of elastomers like rubber. A number of research projects study the application of another type of antiozonants to ...