Over the course of this year through the on-going pandemic, we have been routinely asked our opinion on existing and new technologies to add to the current HVAC systems in an effort to fight COVID-19 and to make the buildings healthier. These new techniques include UV lighting retrofits, filtration system upgrades, and air ionization systems, to name a few. Although all of these upgrades have potential benefits to improve overall IAQ, we feel that the basic principles of IAQ are being overlooked when assessing how to improve the overall health of the indoor environment. Here are a few key components that may serve as a reminder on how to evaluate and maintain good indoor air quality.
The HVAC system is essentially the lungs of a building. Like in our human body, the lungs require a source of fresh air to replenish oxygen to the body. Likewise, buildings require a source of fresh air in order to dilute contaminants, such as carbon dioxide being exhaled by the occupants of the building. We sometimes find that the location of the fresh air intakes to a building are located in areas of potential sources of airborne contaminants, such as loading dock areas where delivery trucks idle allowing combustion contaminants to enter the building. In addition to location of the fresh air intakes, we often see that the systems that control fresh air intake to the building have either been modified or disabled, in many cases due to energy costs savings efforts, as conditioning outside air does increase energy use. Is your building getting enough fresh air?
The HVAC in a building is designed to distribute conditioned air throughout the building in adequate amounts to match each area’s use and occupancy. In commercial and office buildings we find that occupancy and use changes typically occur over time. In many instances over the life of a building, these changes are not addressed with regards to the HVAC system air distribution. This can cause inadequate ventilation in some areas, therefore throwing the system “off-balance”. An HVAC system that is off-balance can have a cascade of negative effects on IAQ, from humidity control issues, thermal discomfort, and air contaminant build-up. Has the building’s HVAC system been evaluated for balance?
As the main system that plays a significant role in the health of a building, without regular maintenance and cleaning, the HVAC system can in turn be a major contributor to poor indoor air quality. Routine inspections on the functionality of the HVAC equipment, coupled with regular filter media changes, and cleaning of heating and cooling elements in the system is essential to maintaining a healthy building. Has the building’s HVAC equipment and filtration systems been inspected and cleaned recently?
In 2020, there has been a heightened awareness in building health and IAQ with the onset of the COVID-19 pandemic. Building owners and property managers have been tasked with how best to keep the building occupants safe and healthy. Government, academia, and industry practitioners have responded with various recommendations that range from occupancy changes to modifications to the operation of HVAC equipment in buildings. Disinfection equipment manufacturers have responded by offering existing and/or new technology systems to assist in making buildings healthier. We believe that all these recommendations and technology have a place on the betterment of building IAQ, however we need to be reminded that they are all based on the premise that the basic principles of good IAQ are already being met in a building.