The world at present is facing a gravest health crisis due to the Covid-19 pandemic. To control its unimaginable transmission worldwide lockdown was implemented resulting in economic deterioration but on the other hand betterment of the environment took place. Therefore this study attempted to analyze the quality of air during the lockdown period and infer its outcome to environment and health. 15 empirical research articles, eight (54%), three (20%), two (13%) and two (13%) from Asia, Europe, South America and North America, respectively have been evaluated. From the studies it was inferred that during the lockdown period, in general, there was a trend of decrease in the level of concentrations of PM₁₀, PM_2.5, CO, NO, NO₂, NH₃, NOx, SO₂ and increase in the concentration level of O₃ in comparison to either the pre-lockdown period or to the previous year(s) records. Marked decrease in the levels of NO, NO₂, NOx were noted. Also PM₁₀, PM_2.5, SO₂ and CO levels were seen to diminish significantly. The main reasons for such decrease were restricted movements of traffic and temporary closure of factories and industries. However, as the thermal power plants were functional during lockdown so improvement of air quality in those areas was not significant. Overall, significant improvement in the air quality was observed during the lockdown which led to better climatic conditions, lesser pollution and improved many seasonal ailments like asthma and other cardio-respiratory issues in people.

中文翻译：

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COVID-19锁定期间的空气质量：因祸得福

由于Covid-19大流行，当前世界面临着最严重的健康危机。为了控制其不可思议的传输，全球范围内实施了封锁措施，导致经济状况恶化，但另一方面却改善了环境。因此，本研究试图分析锁定期的空气质量，并将其结果推论为环境与健康。评估了15篇实证研究文章，分别来自亚洲，欧洲，南美和北美的八篇（54％），三篇（20％），两篇（13％）和两篇（13％）。从研究中推断，在锁定期间，总体上，PM ₁₀，PM _2.5，CO，NO，NO ₂，NH ₃的浓度水平存在下降的趋势。 与锁定前时期或上一年的记录相比，NOx，SO ₂和O ₃的浓度水平增加。注意到NO，NO ₂，NOx水平显着降低。还有PM ₁₀，PM _2.5，SO ₂并发现一氧化碳水平显着降低。数量减少的主要原因是交通流向受限以及工厂和工业暂时关闭。但是，由于火力发电厂在锁定期间处于运行状态，因此这些地区的空气质量改善并不显着。总体而言，在锁定期间观察到空气质量有了显着改善，这导致了更好的气候条件，更少的污染并改善了许多季节性疾病，例如哮喘和其他人的心肺疾病。