In the period 2013–2015, PM 2.5 and PM 10 outdoor and indoor concentrations were measured on 23 days in cold half-year periods, in Kraków, Poland. Air pollution is still a serious health hazard for the inhabitants as Kraków is located in a concave landform and smog episodes occur often in the city during the heating periods, due to poor natural ventilation and frequent air temperature inversions. The PM 10 and PM 2.5 concentrations were studied for very good and very poor weather conditions concerning air pollution. Each subgroup was further divided into cases when the apartments’ windows were kept open or closed. Daily courses of PM 10 and PM 2.5 concentrations were very dynamic. Weather pattern, in particular wind speed and atmospheric stability, largely determined the concentrations of PM 10 in ambient air. The share of PM 2.5 in PM 10 indoor concentrations reached around 70% for both types of weather conditions. The share of indoor PM 10 and PM 2.5 mean concentrations in the outdoor values was higher during good than during poor weather conditions by about 10%.

中文翻译：

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波兰克拉科夫风速和公寓通风对室内 PM10 和 PM2.5 浓度的影响

在 2013 年至 2015 年期间，在波兰克拉科夫的寒冷半年期间的 23 天测量了室外和室内 PM 2.5 和 PM 10 浓度。空气污染对居民的健康仍然是一个严重的危害，因为克拉科夫地处凹形地貌，由于自然通风不良和气温频繁反转，在供暖期间城市经常出现烟雾事件。研究了 PM 10 和 PM 2.5 浓度在非常好和非常差的空气污染天气条件下。每个子组进一步分为公寓窗户保持打开或关闭的情况。PM 10 和 PM 2.5 浓度的每日变化非常动态。天气模式，特别是风速和大气稳定性，在很大程度上决定了环境空气中 PM 10 的浓度。PM 2 的份额。在这两种天气条件下，PM 10 中 5 的室内浓度都达到了 70% 左右。室内 PM 10 和 PM 2.5 平均浓度在室外值中所占的比例在天气条件良好时比在恶劣天气条件下高约 10%。