The Analysis Of The Ward Air Conditioning Environmental Microbial Colony Characteristics And Risk Assessment

Bioaerosols are received great attention in recently years because of the vagilityand the serious social harm.Bioaerosols have different harm due to different particlesize.Due to special environment, special crowd and exposure time, the hospital has aunique research value.This paper aims to study the status quo of bioaerosols in medicalbuilding and to promote building design.Microbiology, epidemiology and public health science and other subjects related toscientific knowledge to monitoring of microbial concentration are integrated used toanalyse the factor of indoor environment effecting on fungi and bacteria concentrationby adjust the air conditioning.Results show that the pollution index is1.94and1.34.Factor analysis showed that indoor temperature and humidity has little effect on themicrobial content and artificial factors are greatly effect.Combined use the architecture environment, microbiology, hospital infectionepidemiology and clinical medicine, using six-stage Andersen sampler to collectbioaerosol samples.Analyse microbial contamination situation of different disease ward,and particle size composition of the ward biological aerosol pollution advantage andmicrobial strains were analyzed, and concluded that the main components of indooraerosol pollution of hospital air conditioning.Through sampling in different wards,,the largest microorganism concentration isin cardiovascular department and respiratory department has the least microorganismconcentration.Most bacteria was collected in the first level, second level and third level,which means the ward bacteria mainly adhere to the particle size of3.3μm aboveaerosol。Most fungi was collected in the third level, fourth level and fifth level, whichmeans the ward bacteria mainly adhere to the particle size of1.1μm~4.7μm。The result showed that Gram-positive accounted for91.3%while Gram-negativefor8.7%for all bacteria。The most prevalent fungi were Aspergillus spp, Penicilliumspp, Cladosporium spp, Candida spp and Trichoderma spp in turn. The most prevalentfungi in pediatric ward were Aspergillus spp, Penicillium spp, Trichoderma spp,Cladosporium spp and Candida spp in turn. The most prevalent fungi in cardiovasculardepartment were Aspergillus spp, Penicillium spp, Cladosporium spp, Candida spp andBipolaris in turn. The most prevalent fungi in respiratory department were Penicilliumspp, Aspergillus spp, Cladosporium spp, Candida spp and Trichoderma spp in turn. Finally using the Monte Carlo simulation method, combining with the measuredindoor microbial contamination, using crystal ball software, obtained the probabilitydistribution of indoor microorganism concentration.According to populationconstitution and breathing rate is different sizes, different bacteria and fungus exposureprobability that may occur.Using the dose-response relationship, based on the uncertainty theory, drawindoor health risk assessment method and the indoor different constitution personnelindoor microbial exposure risk level. Make a basic research for hospital air conditioningbuildings interior risk evaluation.