wind-driven roof turbines a novel way to improve ventilation for tb infection control in health facilities屋顶风力涡轮机一个新奇的办法改善卫生设施的结核感染控制通风.pdfVIP

Wind-Driven Roof Turbines: A Novel Way to Improve Ventilation for TB Infection Control in Health Facilities 1,2 3 1 1 2 4 Helen Cox *, Rod Escombe , Cheryl McDermid , Yolanda Mtshemla , Tim Spelman , Virginia Azevedo , Leslie London5 ´ ` 1 Medecins Sans Frontieres, Cape Town, South Africa, 2 Burnet Institute for Medical Research, Melbourne, Australia, 3 Department of Infectious Diseases and Immunity, Imperial College London, London, United Kingdom, 4 City of Cape Town Health Department, Cape Town, South Africa, 5 University of Cape Town, Cape Town, South Africa Abstract Objective: Tuberculosis transmission in healthcare facilities contributes significantly to the TB epidemic, particularly in high HIV settings. Although improving ventilation may reduce transmission, there is a lack of evidence to support low-cost practical interventions. We assessed the efficacy of wind-driven roof turbines to achieve recommended ventilation rates, compared to current recommended practices for natural ventilation (opening windows), in primary care clinic rooms in Khayelitsha, South Africa. Methods: Room ventilation was assessed (CO2 gas tracer technique) in 4 rooms where roof turbines and air-intake grates were installed, across three scenarios: turbine, grate and window closed, only window open, and only turbine and grate open, with concurrent wind speed measurement. 332 measurements were conducted over 24 months. Findings: For all 4 rooms combined, median air changes per hour (ACH) increased with wind speed quartiles across all scenarios. Higher median ACH were recorded with open roof turbines and grates, compared to open windows across all wind speed quartile