AOT 40 definition
AOT 40 means the sum of the difference between hourly concentrations of ground-level ozone greater than 80 µg/m2 (= 40 ppb) and 80 µg/m2 during daylight hours accumulated from ¥ay to July each year;
AOT 40. (expressed in (μg/m3)∙ hours) means the sum of the difference between hourly concentrations greater than 80 μg/m3 (=40 parts per billion) and 80 μg/m3 over a given period using only the one-hour values measured between
AOT 40. (expressed in (μg/m3).hours) means the sum of the difference between hourly concentrations greater than 80 μg/m3 (= 40 parts per billion) and 80 μg/m3 over a given period using only the one-hour values measured between 0800 hours and 2000 hours Central European Time each day;