Objective To explore the status of PM 2.5 pollution in school classrooms and the student exposure level, and to provide basic data to safeguard the health of students.
Methods This study continuously monitored the PM 2.5 levels of 16 naturally ventilated classrooms in eight primary and secondary schools in Jiamusi for one academic year using an online environmental monitoring instrument. At the same time, outdoor PM 2.5 data was captured for comparative research, and student exposure to PM 2.5 during school hours was evaluated.
Results The average concentration of PM 2.5 in the classroom in the spring and autumn semesters was (26.93±24.7) and (31.85±30.37) μg/m 3, respectively, and the indoor/outdoor ratio ( I/O) was 0.92 and 0.95, respectively, which indicated a strong correlation between them. The daily average concentration of all classrooms during both semesters was (28.93±26.85) μg/m 3, which was slightly higher than the average concentration of (27.53±26.53) μg/m 3 during the daytime when students were in school. In addition, the concentration on workdays was higher than that observed on weekends, and this was termed the “weekend effect”. The indoor PM 2.5 concentration was lower on higher floors. The comprehensive exposure concentration of students during school was 28.48 μg/m 3 in spring semester and 31.87 μg/m 3 in autumn semester.
Conclusion PM 2.5 levels in the classrooms varied according to time, the horizontal space, and the vertical space, and the level of indoor PM 2.5 pollution largely depended on outdoor pollution sources. Differences in PM 2.5 exposure were observed between.
【摘要】 目的 了解学校室内 PM 2.5 污染状况和学生暴露水平, 为学生健康防护提供基础数据。 方法 通过在线环境监 测仪对佳木斯 8 所中小学 16 间自然通风教室的 PM 2.5 进行为期 2 个学期的连续监测, 同时抓取室外 PM 2.5 数据进行对比研 究, 对学生在校期间暴露量进行评价。 结果 春、秋两学期教室内 PM 2.5 平均质量浓度分别为 (26.93±24.7) 和 (31.85± 30.37) μg/m 3, 教室内外 PM 2.5 I/O值分别为 0.92 和 0.95, 存在强相关性。两学期所有教室的全天 PM 2.5 平均质量浓度为 (28.93±26.85) μg/m 3, 略高于白天学生在校期间的 (27.53±26.53) μg/m 3, 且工作日质量浓度高于周末。随着楼层升高, 室 内 PM 2.5 质量浓度逐渐下降。学生在校期间的累积暴露量, 春季学期为 28.48 μg/m 3, 秋季学期为 31.87 μg/m 3。 结论 教 室内 PM 2.5 随时间、水平空间与垂直空间的变化会有所不同, 且室内 PM 2.5 的污染程度极大依赖于室外污染源; 春、秋两学期 学生在校期间 PM 2.5 暴露量有所差异。