What can ventilation do?

Abstract

Can influenza virus such as 2009 A (H1N1) be transmitted by the airborne route? How important is building ventilation as compared to vaccination and quarantine in infection control? SARS, avian flu and 2009 A(H1N1) viruses might have jumped from animals or birds to human, but it is mostly in buildings that these viruses can spread among us. The 2009 A(H1N1) influenza pandemic has become a new reminder for the possible rapid spread of emerging respiratory infectious diseases in modern built environment. Lower respiratory infections and tuberculosis still are and will remain among the top 7 causes of world disease burden in the near future. Since the 2003 SARS epidemic, there has been a renewed interest in engineering control of respiratory airborne infection such as building ventilation. In this talk, we will revisit the fascinating evolution of our understanding of airborne infection and ventilation, and what we can learn from it, the basic and evolving concepts of airborne transmission and droplet transmission, examples of large SARS and 2009 A(H1N1) outbreaks, the importance of body microenvironment, the effectiveness of ventilation, UVGI and HEPA, emerging issues such as new ventilation technologies, implications for commissioning and maintenance, and finally suggestions of the important roles that ASHRAE community can play in collaboration with WHO and CDC.