论文部分内容阅读
目的了解区域室内空气PM2.5浓度水平及分布特征。方法选择住宅、学校、办公场所共3个室内监测点和1个室外监测点(设在办公室外),采用重量法测定PM2.5与PM10的质量浓度。监测时间为2013年5月至2014年4月,每月连续监测7d,每天连续采样24-h。结果室内监测点PM2.5浓度总体均值和中位数分别为89μg/m3和61μg/m3;PM2.5浓度中位数Wilcoxon检验结果:住宅(69μg/m3)高于学校(58μg/m3)和办公室(50μg/m3),学校与办公室差异无统计学意义,办公室外(92μg/m3)高于室内;依据GB-3095-2012规定的浓度日均限值二级标准评价:χ2检验显示室外PM2.5浓度超标率(60.7%)高于室内(41.7%),室内PM2.5浓度超标率高于PM10(22.9%);4个监测点PM2.5日均浓度变化较大但变动趋势一致,共监测到9次PM2.5重度污染(>150μg/m3),累计室内17d(20.2%),室外24d(28.6%)。月均PM2.5浓度呈现2-3月(冬季)最高、7-8月(夏季)最低。Wilcoxon检验室内PM2.5/PM10中位数(84.7%)高于室外(64.1%)。t检验I/O均值显示PM2.5(67.2%)>PM10(53.9%)。室内与室外PM2.5浓度呈正相关,回归方程为y(μg/m3)=0.841x-14.804。结论监测地点室内空气污染较严重;室内空气PM2.5浓度与室外浓度密切相关,随着北京室外PM2.5浓度的季节性变化,室内浓度亦呈现冬季高夏季低的特点。
Objective To understand the PM2.5 concentration and distribution in indoor air. Methods A total of 3 indoor monitoring points and 1 outdoor monitoring point (outside the office) were selected from houses, schools and offices. The mass concentrations of PM2.5 and PM10 were determined by gravimetric method. Monitoring time is May 2013 to April 2014, monthly continuous monitoring 7d, continuous sampling 24-h daily. Results The median and median of PM2.5 concentration in indoor monitoring sites were 89 μg / m3 and 61 μg / m3, respectively. The median of PM2.5 concentrations was higher in Wilcoxon test (69 μg / m3) than in schools (58 μg / m3) and Office (50μg / m3), school and office no significant difference, outside the office (92μg / m3) higher than the indoor; according to GB-3095-2012 concentration daily average limit of secondary evaluation: χ2 test showed outdoor PM2 .5 The over-standard rate (60.7%) was higher than the indoor rate (41.7%), the indoor over-standard rate of PM2.5 was higher than that of PM10 (22.9%), A total of 9 PM2.5 heavy pollution (> 150μg / m3) were detected in 9 days, accumulated indoor 17d (20.2%) and outdoor 24d (28.6%). The monthly average PM2.5 concentration showed the highest in February-March (winter), the lowest in July-August (summer). The median of PM2.5 / PM10 in Wilcoxon test room (84.7%) was higher than that in the outdoors (64.1%). The t-test I / O mean showed PM2.5 (67.2%)> PM10 (53.9%). The indoor and outdoor PM2.5 concentrations were positively correlated, the regression equation was y (μg / m3) = 0.841x-14.804. Conclusion The indoor air pollution in the monitoring sites is more serious. The concentration of PM2.5 in indoor air is closely related to the outdoor concentration. With the seasonal variation of outdoor PM2.5 concentration in Beijing, the indoor concentration is also characterized by high summer and low summer.