20 Apr 2020


COVID-19 & HVAC Position Statement

Dr. Rajiv Sahay, Ph.D., FIAS, CIAQP
Laboratory Director
EDLab at Pure Air Control Services, Inc,
4911-C Creek Side Drive
Clearwater, FL 337620

Most regulations and codes of HVAC are designed to improve the overall energy efficiency and environmental sustainability of the system. However, there has been no emphasis given by the regulators and the building owners on the hygiene assessment due to microbial and other potential agents that may adversely influence the building’s health and hygiene. Maintenance of HVAC to address the microbial influence is exceedingly becoming important as it may act as an accumulation and dissemination hub of infectious agent that may impact the occupant health adversely. Currently, coronavirus (COVID-19) is identified as a potential infectious agent that can infect occupants leading to death in extreme conditions. The ventilation flow rate in energy tight buildings is directly proportional to the spread of air-borne infectious agents including the recent escalation of COVID-19 issue.

Droplets generated from a person infected with coronavirus is identified as a primary source of dissemination and accumulation in occupiable space. While most of the larger droplets travel short distances (< 1 m), some of the smaller size nuclei may enter in air-conveyance systems only to settle on coils, ducts and other HVAC components due to favorable conditions (including biologically active materials) or spread through ductwork of air distribution systems. A wide range of biologically significant entities such as viruses, bacteria, mold, mites, insects, protozoa, algae, other cystic life forms and others are generated especially in damp and dirty ducts system both in residential as well as commercial or institutional settings that can provide breeding ground and the transmission of such infectious or disease causing agents including the virus. It can remain in building if not removed appropriately due to air circulation especially where ventilation is mechanically control.

It is estimated that typically the air change rate (ACR) is four times per hours in a mechanically ventilated building; however, it may be up to 8-10 times in hospital and other healthcare settings. Routine HVAC maintenance like regular filter changes and deeper, more focused hygienic cleaning such as PURE-Steam coil cleaning and PURE-Decon electrostatic spray treatments can potentially reduce the risk of coronavirus (COVID-19) spreading into occupiable spaces. Therefore, when developing a proactive program for good IAQ practices it is encouraged to evaluate the hygienic condition of the HVAC system. In the event of undesirable sanitary conditions in the HVAC system due to both a-biological and biological contaminants call a professional environmental remediation company that specializes in restoring HVAC systems to mitigate the issue(s).

For more information please call 1-800-422-7873 Ext. 301 or email us.