جستجوی مقالات مرتبط با کلیدواژه « 2 میکرون » در نشریات گروه « محیط زیست »

One of the most significant human health risks is the pollution of enclosed spaces. The high density of people and the variety of products available in exhibition halls make them perfect locations for the accumulation of polluting particles. Air pollutants are mixtures of suspended solids and liquids in the air, which vary in size, shape, and chemical composition.This study was conducted to measure PM2.5 and PM10 pollutants particles in four seasons consecutively throughout the year in Hall No. 38 of the Tehran International Exhibitions Company (TIEC). This goal was achieved by establishing an (SKC) air sampling pump at breathing height and comparing the results with the standard 24-hour analysis. According to the results, the average PM10 value in the autumn season was 160.8 µg cm-3, which was reported as higher than the standard 24-hour exposure value. There was also a maximum measured value of 198 µg cm-3 of PM10 during the mentioned season. The findings showed that the average PM2.5 value in the same season was 38 µg cm-3, which was reported as higher than the standard 24-hour exposure value (35 µg cm-3).It was mainly the effect of outdoor air quality on the indoor air in halls and the heating system that contributed to the increase in particulate matter in the autumn. According to the studies, it was found that outdoor and indoor air in halls is directly related. Therefore, Tehran Exhibition halls and other similar sites should continually monitor the level of air pollutants to reduce their health effects.

One of the significant challenges metropolises faces is air pollution, which has many adverse effects on human health and the environment. Karaj, as an industrial city situated close to the country's major industries and power plants, is severely affected by air pollution from both mobile and stationary sources. This study measured air quality in stations equipped with the analyzers of four gaseous pollutants, including ozone, carbon monoxide, nitrogen dioxide, and sulfur dioxide, along with two particulate pollutants, including particulates smaller than 2.5 and 10 microns. Furthermore, the city's air quality index, obtained from the total of monitoring stations, was analyzed. The study finds that particulate matter smaller than 2.5 microns and ozone are the main pollutants in Karaj in hot and cold seasons, respectively. The other pollutants exceed the allowable air quality index, rarely. For a period of one-year, particulate matter smaller than 2.5 microns and ozone put the air quality index in the range of unhealthy for sensitive groups and unhealthy for the entire city of Karaj for 94 and 18 days, respectively. Due to the secondary nature of Karaj's main pollutants, such as ozone in the warm season and a high portion of suspended particles smaller than 2.5 microns in the cold season, it is necessary to reduce air pollution through modeling that incorporates photochemical reactions in the atmosphere.