Centralised ventilation system for preventing nosocomial transmission of tuberculosis in a hospital isolation ward

Abstract

Centralised ventilation increases indoor air quality for a healthy hospital indoor environment by supplying fresh air from outside to inside the isolation ward and dispose out the stale air. Poor ventilation for isolation wards can increase risks of nosocomial transmission. Thus, the aim of the study is to develop a healthcare setting layout in healthy indoor air environment in order to prevent the nosocomial transmission of Tuberculosis (TB) by centralised mechanical ventilation system for TB isolation ward. This study was conducted at Hospital Sultanah Aminah, Johor Bahru and four stages of qualitative and quantitative research methods were involved. The first step was the interview and questionnaire stage with Healthcare Workers (HCWs) at TB Isolation Wards and Respiratory Specialist Clinic. The second stage was to determine the existing TB isolation ward. The third step was mapping rooms’ temperature with imaging thermal infrared. Finally, the design and installation of a mock up room with a centralised ventilation system was evaluated. Thirty nine HCWs answered the five Likert Scale questionnaire survey which identified indoor air environment sustainability factors. Four factors have been selected to choose the most effective room as a mock up. Based on findings, single bedroom was the most effective one based on calculation of air density per patient. The mock up design for selected isolation ward SB2 is 3.000 m length x 2.000 m width x 3.144 m height. Room temperature changes were detected using temperature mapping when the windows set to close and open. A mock up room manages the route of airborne TB transmission and has been designed and installed centralised ventilation system for three persons (1 patient and 2 HCWs) in one time, 15.7 Air Change per Hour (ACH) more than 12 ACH specification requirement, whereby the performance ventilation indicator carbon dioxide does not exceed 1,000 ppm in one time. However, relative humidity and temperature exceeded their acceptable range depending on the surrounding environmental conditions. The study is concerned about the HCWs to protect them by preventing nosocomial TB transmission. The mock up of innovations designed based on environmental and engineering controls has been shown to help in eliminating Building Related Illnesses (BRIs). Thus, it is suggested that this mock up is recommended to function its role not only in Hospital Sultanah Aminah but also in other hospitals.