Élaboration d'une stratégie de ventilation pour l'élimination efficace des bioaérosols dans une unité de bronchoscopie

Abstract

The quality of the indoor air is one of the most encountered problems in our day. People spend more than 90% of their time inside buildings. Building engineers work to provide the best comfort conditions to building occupants. Their main objectives are to improve the ventilation efficiency and optimize the indoor air quality. Exposure to gaseous or particulate contaminants present in the air inside buildings is a very important risk factor for a number of respiratory symptoms. In the hospital sector, the air quality is of major importance. Several sources of pollution and contaminants exist in such buildings. In particular, bronchoscopy units raise concerns since bronchoscopy procédures can induced severe coughing for the patient that will generate a multitude of airborne microorganisms. The objective of this work is to model the aerodynamic behavior of bioaerosols during a bronchoscopy procedure and evaluate the influence of air change per hour on the bioaerosols concentration. Numerical simulations of this project were done using the Fire Dynamic Simulator Software (FDS), which is based on the large eddy simulation method (LES). The study was conducted using two transport models and four ventilation scenarios. The tracer gas method was used to determine experimentally the mean age of air in the bronchoscopy unit studied. These results were also used to validate the numerical code. The main results of this study show the influence of the air change per hour on the bioaerosol concentration in the bronchoscopy unit. The exposure level of the hospital staff, the air exchange coefficient, the air extraction rate, the age of air and the amount of contaminant deposited on walls were determined. From these results, recommendations were made to ensure an improvement in the ventilation system efficiency and a good air quality for the hospital staff.

Date	6 Jun 2014
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Stéphane Hallé (Supervisor)