大学校园室内大气NO_(2)污染特征及学生暴露水平

Characteristics of Indoor Air NO_(2)Pollution and NO_(2)Exposure Levels for Students on Campus

采用被动法监测沈阳某高校校园学生寝室、教室、南门和北门门卫室、食堂室内大气NO_(2)两周平均质量浓度的季节变化特征,同时记录临近空气质量监测站室外NO_(2)小时平均质量浓度,评估学生NO_(2)暴露水平.结果表明:食堂的室内NO_(2)质量浓度最高(106.7~321.2μg/m^(3)),南门和北门门卫室次之(分别为30.5~148.3μg/m^(3)和39.3~138.9μg/m^(3)),学生寝室和教室最低(分别为22.1~40.9μg/m^(3)和22.6~42.2μg/m^(3));食堂和门卫室室内NO_(2)质量浓度具有明显的季节变化特征,各季节的NO_(2)质量浓度基本呈现冬季>秋季和春季>夏季的特征;燃气和香烟的燃烧分别是食堂和门卫室室内大气NO_(2)的重要来源,可引起较严重的室内NO_(2)污染;学生NO_(2)暴露水平为26.5~53.3μg/m^(3),表明学生基本不受NO_(2)污染影响.通过加强食堂室内外通风,缩短在食堂的停留时间等可降低学生的NO_(2)暴露水平.

Passive samplers were employed to monitor the seasonal variations of two-week mean NO_(2)concentrations in a dormitory,a classroom,the South-and North-Gate Guard-rooms,and a canteen on campus of Shenyang City.Meanwhile,hourly mean outdoor NO_(2)concentrations at the nearest air quality monitoring station were retrieved from a website.The NO_(2)exposure levels for the students of the campus were calculated.The results showed that the highest indoor NO_(2)concentrations(106.7 to 321.2μg/m^(3))occurred in the canteen,followed by those in the South-and North-Gate Guard-rooms(30.5 to 148.3μg/m^(3)and 39.3 to 138.9μg/m^(3),respectively),and the lowest cocentrations occurred in the dormitory and the classroom(22.1 to 40.9μg/m^(3)and 22.6 to 42.2μg/m^(3),respectively).The NO_(2)concentrations in the canteen and the guard-rooms showed an obvious seasonal variation,with the order of concentrations in different seasons being generally winter>autumn and spring>summer.Combustion of liquefied gas and cigarette smoking were the main sources of indoor air NO_(2)for the canteen and the guard rooms,respectively.These sources could lead to severe indoor NO_(2)pollution.The NO_(2)exposure levels for the students of the campus ranged from 26.5 to 53.3μg/m^(3),suggesting that they were generally unaffected by NO_(2)pollution.Such exposure levels can be reduced by enhancing the indoor-outdoor ventilation of the canteen,reducing the residence time spent in the canteen,among other methods.