Ventilation In Dormitories And Its Association With Airborne Transmission Of Respiratory Infections

Dormitory is the important place for college students to study and stay.Dorm environment has great influence on the psychological and physical health and learning efficiency of students.Dormitory has natural ventilation system.This crowded environment with insufficient ventilation may cause propagation of respiratory infections.This paper is to survey the dormitory ventilation and its association with respiratory infections.This study was carried out at Tianjin University,Tianjin City,China,from May2015 to January 2016,which consisted of two phases,Phase I is questionnaire survey,phase?is dormitory environment test.In Phase I,the health conditions of students and dormitory environment were reported on the self-administrated questionnaires by2951 students living in 998 dorm rooms in 12 buildings on the campus.Students'health problems consisted of respiratory infections,sleeping quality and sick building syndrome et a1.Dormitory environment problems mainly include the dormitory dampness,perception of odors and the frequency of opening windows for ventilation.In phase?,based on the date obtained from questionnaire survey,242 dorm rooms in11 buildings was selected to inspect,to measure indoor air temperature,air relative humidity and CO₂ concentration.Ventilation rates were calculated on the basis of CO₂concentrations.SPSS?Statistic Package for the Social Science?was used for data analysis.In Phase I,there were significant associations between visible mould/damp stains,water damage and common colds,influenza.For college students,higher incidences of common cold and influenza were reported in spring and winter,with the lowest incidence in summer.In Phase II,86.0%of the measured dorm rooms had an out-to indoor air flow rate less than the Chinese standard of 8.3 L/s per person during the heating season,while in summer 48.3%rooms had ventilation rate less than this standard.There were significant associations between ventilation rate per person at night in summer and infections of common cold?P=0.046?and influenza?P=0.031?in summer.The incidence of common cold and influenza were higher and the duration were longer in rooms with higher CO₂ concentration,but there were no significant relations between them.There were significant associations between relative humidity in summer daytime and common cold?P=0.029?infections.The incidence of common cold and influenza were lower and the duration were shorter in rooms with higher relative humidity.Preliminary understanding of the health condition of students and the dorm environment in college can be obtained from this study,as well as the relationship between the ventilation rate and the respiration infection of students.It can provide the evidence for the improvement the dorm environment and the prevention and control of respiratory diseases.