ABSTRACT
Objective:To evaluate the implementation effect of the "Shanghai Construction Project Centralized Air Conditioning and Ventilation System Hygiene Evaluation Specification （Trial）" （hereinafter referred to as the "standard"）. Methods:The "Centralized Air Conditioning and Ventilation System Hygiene Evaluation Report Score Sheet" was used to compare the quality of air conditioning hygienic evaluation reports before and after the implementation of the standard. Results:After the implementation of the standard， the total score of the air conditioning health evaluation report was significantly higher than that before the implementation （t=3.164， P=0.002）. The scores of format， general theory， engineering analysis and suggested conclusion after the implementation were all higher than before the implementation （t=3.701， 2.012， 2.152， 2.450， respectively， all P<0.05）. The difference in scores of evaluation process was not statistically significant between before and after the standard implementation （P=0.465）. Conclusion:After the implementation of the standard， the quality of air-conditioning health evaluation reports has significantly improved.
ABSTRACT
Objective To assess the hygienic status of the central air conditioning ventilation system in public places by fuzzy comprehensive evaluation method.Methods According to the comprehensive evaluation method of public place (WS /T 199—2001),a fuzzy comprehensive evaluation method was applied to evaluate central air conditioning ventilation systems in 15 large public places of Jinhua City.Results The qualified rate of central air ventilation system was 53.30%, and the qualified rates of total number of bacteria,the fungi,β-hemolytic streptococcus in air blow and Legionella bacteria in the cooling water all reached 100.00%.At the same time,the qualified rate of bacteria,fungi and dust volume in internal surface of pipe were 93.33%,86.67% and 80.00% respectively.The qualified rate of PM10 was 86.67%. Among 15 central air conditioning ventilation systems,13 systems were evaluated as level Ⅰ,and the other two was as level Ⅱand Ⅳ respectively.TAAlso,14 evaluated units got the fuzzy comprehensive indexes of central air ventilation less than 0.5.Conclusion The hygiene status of central air conditioning ventilation system in Jinhua is acceptable,and the management of hygiene quality should be strengthened.
ABSTRACT
Objective To know the air supply quality of central air-conditioning ventilation system in building before and after cleaning.Methods Three sets of central air-conditioning ventilation systems were selected from a building randomly and 3 air supply ways were selected in each system for the determination of inhalable particulate matter(PM10) and microorganisms in air before and after cleaning.Results After cleaning,the unqualified rate of air quality increased from 11.1%(before cleaning) to 77.8%.The mean value of PM10 increased from 0.051 mg/m3(before cleaning) to 0.083 mg/m3,the median of total account of bacteria and fungus increased from 150 cfu/m3 and 13 cfu/m2(before cleaning) to 570 cfu/m3 and 110 cfu/m3 respectively.Conclusion The air supply quality of central air-conditioning ventilation system in building may be damaged by cleaning if the operation is not in the right way.