Restricted accessResearch articleFirst published online 2026
Comparative performance study of traditional unidirectional airflow and novel variable temperature and velocity air supply systems on thermal comfort of medical staff in operating room
Thermal comfort of medical staff in operating room can affect the work efficiency and have an impact on the success of surgeries. Due to the varying thermal comfort requirements of medical staff with different responsibilities, unidirectional airflow system cannot meet the thermal needs of all personnel. Therefore, a novel variable temperature and velocity air supply (VTVA) system has been introduced to investigate its impact on thermal comfort of medical staff. Since direct measurement of indoor thermal environment parameters during actual surgeries is impractical and difficult, Computational Fluid Dynamics (CFD) simulation method was adopted for this study. The distribution of thermal environment parameters and PMV-PPD indicators between unidirectional airflow and the VTVA systems were compared. It indicates that the VTVA system can create multiple thermal environment zones in the operating room, significantly improving the thermal comfort level of medical staff. When the air supply temperature on both lateral sides was within the range of 21.0–23.0°C, satisfactory thermal comfort was attained for the surgeon and the anaesthetist. CFD numerical method is an effective tool for predicting the thermal comfort of medical staff in operating room. This study provides a theoretical basis for optimizing the design of air supply systems in operating rooms.
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