OBJECTIVE  To investigate the changes of air aerosols in the digestive endoscope cleaning and disinfection room under real working conditions and observe the purification effects of aerosols under different ventilation and disinfection modes.

METHODS  Under the real working conditions (with both the air conditioner and recirculating air disinfection machine under the working mode), the air samples were collected every 1 hour from 8∶00 to 16∶00 from the digestive endoscope cleaning and disinfection room of Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine from May 2023 to Oct. 2023; the contents of particulate matters (PM) and microorganisms in the air were detected. At the busiest moment of the cleaning and disinfection room, the air was respectively sampled from the cleaning and disinfection room with the working condition modes of air condition systems, recirculating air disinfection machine or natural ventilation before the starting of systems and after the work for 0.5 hour, 1 hour and 2 hours. The contents of PMs and microorganisms were detected.

RESULTS  The PM_0.5 concentrations during various time periods met the Grade 9 ISO clean room standard (≤35, 200 particles/L) under the real working conditions, and the content of airborne viable particles also conformed to the Class Ⅲ environmental requirements (≤500 CFU/m³). All of the three ventilation and disinfection methods showed certain effects on purification of the contents of PM_0.5 and microorganisms after the ventilation for 2 hours, the contents of PMs and microorganisms of the air disinfection machine group decreased most remarkably, followed by the air conditioner group, the natural ventilation group the least. There were no significant differences in the PM concentration and the content of microorganisms among the three groups at the time points; there were only significant differences in the PM concentration and the content of microorganisms of the air disinfection machine group after the ventilation for 2 hours, 0.5 hour and 1 hour(P < 0.05).

CONCLUSIONS  Both the air conditioning systems and recirculating air disinfection machine under the working condition mode have certain effect on purification of the contents of PM and microorganisms, and the specific effect need to be further studied. The implementation of multicenter dynamic surveillance with the help of intelligent techniques may provide reference for the optimization of ventilation and disinfection strategies.