Suitability evaluation on laminar airflow and mixing airflow distribution strategies in operating rooms: A case study at St. Olavs Hospital

Operating room (OR) is an indispensable department in a hospital, while its ventilation system is an important engineering solution to ensure safety for surgical procedures. Suitable ventilation system in the OR should be defined as using the minimum energy consumption and lifecycle cost to meet both the requirements of clean air for safe surgeries and comfort for occupants. Therefore, this study aims to develop a flexible evaluation framework on the suitability evaluation for ventilation system performance in ORs from a holistic view instead of one aspect only. To achieve the objective, we adopted analytic hierarchy process (AHP) and fuzzy comprehensive evaluation (FCE) methods and conducted suitability evaluation for two ORs with laminar airflow (LAF) and mixing ventilation (MV) system in St. Olavs Hospital, Norway. The evaluation includes seven indexes under three main aspects: ventilation effectiveness, energy consumption and users? satisfaction. The comprehensive evaluation results are obtained through site measurements during mock surgeries, data collection and calculation as well as the questionnaire survey. Due to the unsatisfactory performance in energy consumption and thermal comfort indexes, the evaluation result of the suitability performance of the case OR with MV system was ?unsuitable? while the one with LAF system was ?suitable?, which reflects the situation that the energy consumption and thermal environment are sacrificed, although a clean and safe operation environment is guaranteed. The evaluation can provide basis for the commissioning of the ventilation system in the ORs of St. Olavs Hospital and provoke thinking of the ventilation system design and operation in the future.