Your HVAC System, the Flu, and You

on July 20, 2009 in Building Maintenance Industry News, HVAC Maintenance and Efficiency, Sick Building Syndrome

Keeping your HVAC system free of harmful contaminants may be more needful now than ever, as the H1N1 influenza virus stalks the globe and becomes a true pandemic. The original media feeding frenzy over the outbreak was a bit unfortunate, since it created a “Boy Who Cried Wolf” effect that may cause people to lose focus on the quiet flow of headlines. Such headlines indicate that a new strain of swine flu is gaining momentum and demands precautions.

(See, for example, “Swine flu virus unpredictable, experts warn,” The Gazette, Montreal, Canada, July 8, and “Pandemic Flu,” The Washington Post, June 28.)

This being the case, you need to be extra aware of the status of your HVAC system right now. Construction Week online carried an article last month about the need for flu prevention treatment in HVAC systems. It stressed the value of high-output UV-C lights installed in the system, since these lights

emit enough energy to penetrate even the tiniest microbe to destroy its DNA and RNA, thereby killing or deactivating it. In a typical building with four to five air changes per hour, UV-C energy can destroy more than 90% of infectious microbes with each air change, reducing them to a level far below what it takes to infect most people. It works against all strains of influenza (including bird or avian flu), other viruses (including colds, SARS, measles and German measles), and bacteria (including TB, Legionella, pneumonia and whooping cough). Most hospitals use 15 to 20 air changes per hour. In these environments, UV-C is even more effective, and can also reduce the incidence of nosocomial (hospital-acquired) infections.

The EPA is getting in on the act, too. Last month they offered a presentation entitled “Swine H1NI Influenza A: Transmission of Viruses in Indoor Air: HVAC System Protection Options” (pdf), which discussed the role that building HVAC systems can play in pandemic flu infection mechanisms by creating air currents that keep moisture droplet nuclei airborne indefinitely, thus providing a way for the virus to circulate around the building. They recommend the use of UV-C lights combined with mechanical filters as a great way to kill the virus.

Along with the above information, other resources are surely available to help you learn what you need to know.

Matt Cardin, Goodway Blogging Team