Indoor Air Quality in a Real Operating Theatre under Effective Use Conditions

Carla Balocco, Giuseppe Petrone, Giuliano Cammarata, Pietro Vitali, Roberto Albertini, Cesira Pasquarella

Department of Biomedical, Biotechnological and Translational Sciences, University of Parma, Parma, Italy.
Department of Clinical and Experimental Medicine, University of Parma, Unit of Medical Immunology, University Hospital of Parma, Parma, Italy.
Department of Industrial Engineering, University of Catania, Catania, Italy.
Department of Industrial Engineering, University of Firenze, Firenze, Italy.
Hospital Hygiene Unit, University Hospital of Parma, Parma, Italy.

DOI: 10.4236/jbise.2014.711086                

Abstract

The aim of this study is to investigate the impact of surgical staff on the indoor air quality in a uni-directional ventilation Operating Theatre (OT). Experimental measurements of particles and microclimate were acquired at rest and in operational conditions. The real OT (operational) use was simulated by a sham hip arthroplasty. CFD simulations were carried out outlining the studied environment used for experimental measurement campaign. A standard k-ε closure scheme based on RANS equations was implemented to solve the velocity and pressure field using an eddy viscosity approach. Temperature and relative humidity distributions were also computed keeping into account sensible and latent heat sources inside the OT. An Euler-based approach was applied to solve the concentration fields of gaseous contaminant and small particles (up to 5 μm in diameter) in the indoor air. An innovative strategy is proposed to estimate, by an iterative comparison between experimental data and numerical results, the emission rate of particles (differentiated by diameters) released by the occupants to be considered as source terms in the numerical model. Compliance with literature evidence concerning thermal and velocity fields and CO₂ concentration was confirmed. From our analyses, some IAQ indexes were deduced, allowing monitoring of the local and overall OT air quality level supplied by the ventilating system during real operational conditions. The highest values of microbial air contamination were recorded during surgical activity; nevertheless, results showed the suitability of the ventilation system in providing the expected air quality.

Keywords

Experimental Measurements, Numerical Simulation, CFD, Real Operating Theatre, Particles, IAQ Indexes

Conflicts of Interest

The authors declare no conflicts of interest.

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