集中空调通风系统对公共场所室内PM_(2.5)浓度的影响

Influence of centralized air ventilation system on indoor PM_(2.5) concentration in public places

目的探索集中空调通风系统对公共场所室内PM_(2.5)浓度的改善效果及其影响因素。方法选取11家设置和6家未设置集中空调通风系统(对照组)的公共场所经营单位作为监测点,利用问卷调查收集基础资料,每周对其室内外PM_(2.5)浓度进行监测,通过非参数检验等方法分析集中空调对室内PM_(2.5)浓度水平的影响。结果设置集中空调通风系统室内相对室外PM_(2.5)浓度平均减少值优于对照组(Mann-Whitney U检验,P=0.021);不同距上次清洗时长组间PM_(2.5)浓度平均减少值存在差异(Z=18.770,P=0.016);中效新风口滤网对降低室内PM_(2.5)浓度比初效滤网能起到更优的效果(Z=-3.354,P=0.001);不同组间新风口滤网清洗频率在降低室内PM_(2.5)浓度的作用上存在差异(Z=14.167,P=0.007),每2个月清洗1次的频率最佳。结论合理使用集中空调通风系统,定期清洗、使用更高过滤等级的滤网并保持最佳清洗频率能有效降低室内PM_(2.5)浓度,有助于改善室内空气质量。

[Objective] To explore the improvement effect of centralized air ventilation system（abbreviated as CAVS）on indoor PM2.5 concentration in public places,explore the influencing factors.[Methods]11 public places with CAVS were selected as monitoring sites and 6 public places without CAVS were collected as the control group. The basic data were collected through ques-tionnaire. Indoor and outdoor PM2.5 concentration was monitored weekly. The non-parametric test was used to analyze the influence of CAVS on indoor PM2.5 concentration.[Results]CAVS effectively reduced indoor PM2.5 concentration as compared with control group（Mann-Whitney U test,P=0.021）. There was significant difference in reduction of PM2.5 concentration among different cleaning length groups（Z=18.770,P=0.016）. The medium efficiency filter had better effect in reducing indoor PM2.5 concentration as compared with primary filter（Z=-3.354,P=0.001）.There was significant difference in effect of reducing indoor PM2.5 concentration among different groups in cleaning frequency of the fresh air inlet filter（Z =14.167,P =0.007）,and bimonthly maybe the best choice.[Conclusion]Reasonable use of CAVS,regular cleaning,filter with higher efficiency and keeping the best cleaning frequency can effectively reduce the indoor PM2.5 concentration and improve indoor air quality.