The Influence of the Bed with a Semiopen Hood on Bacteria Removal in a Negative-Pressure Isolation Room

Abstract

This study numerically investigates the influence of a sickbed with a semiopened hood on bacteria removal in a negative-pressure isolation room. The parameters include air change rate, lying style, the length and height of hood, flow rate allotments, and the positions of outlets. The results show that the hood has excellent effect on the removal of contaminated air, which is much better than the case without hood. The flow field of patient's face up cough is very different from face side cough, and the contaminated air cannot be removed properly through one air outlet. There are three outlets on the hood, set straight above the patient's face and at both sides. The allotment of the exhaust flow rate of the upper outlet to that of side outlets is suggested to be 4 : 6. When the total air change rate is above 6 ACH, the hood length has slight influence on pollutant removal. The increase of hood height has a negative impact when the patient coughs lying on back. When the side exhaust flow rate is high, the hood height has a slight impact for face side cough. The recommended air change rate for the negative-pressure ward with sickbed hood is above 5 ACH.

Evaluation of UR-UVGI System for Sterilization Effect on Microorganism Contamination in Negative Pressure Isolation Ward

“…According to Lindsley et al [11], who investigated the distribution of airborne microorganisms that cause respiratory diseases in medical facilities, airborne microorganisms are fine particulates that can spread to adjacent areas through in-patient respiration and other means possibly contributing to the spread of infection, thus necessitating the outline of control measures. In this context, special facilities such as negative pressure isolation wards have been established as preventive measures against infection, and corresponding studies on ventilation have been conducted [12,13]. Fletcher et al [14] have strongly emphasized the importance of airborne contamination, noting the issue of infection within hospitals and medical facilities as a serious problem.…”