Understanding HVAC & Indoor Air Quality Technologies & Practices

Strategy Overview

A building’s heating, ventilation, and air conditioning (HVAC) system has always been known as the mechanical system in the building that appropriately heats and/or cools the building and its occupants. However, the perceived role of the HVAC system is changing. The recent COVID-19 pandemic has placed a lens on potential building impacts to occupant health and safety, and therefore, on the increased focus on the role of the HVAC system and how it can assist in the indoor air quality (IAQ). Organizations such as ASHRAE and the CDC have come out with many new or updated guidelines or standards specific to HVAC systems and IAQ, and many studies exist from other impartial organizations such as the National Institute of Health (NIH) or the Environmental Protection Agency (EPA).

Many different types of IAQ technologies and practices are available for many different types of HVAC systems. Which technology or design should be used? Which is the most effective? Which will keep my occupants safe? These are great and viable questions and attempting to dig through the research and appropriately answer for your unique situation can be a daunting task for companies. This white paper will assist with this research, analysis, and recommendations.

There are key considerations we should all review when deciding which technology or strategy would be best for our buildings:

1. Of the available IAQ technology types for commercial HVAC systems, and specifically those types discussed in this white paper (ultraviolet light, air ionization, high filtration, high ventilation and humidity control), none will completely remove all airborne particulates or prevent all microbial build-up. However, each of these technologies or strategies can make an impact on IAQ, as well as on the operation of the HVAC system.
2. Most manufacturers of IAQ systems have conducted studies as to the effectiveness of the systems they manufacture. However, most of these studies are not peer-reviewed, or conducted by impartial third parties. In fact, many of these studies have been funded and/or conducted by the manufacturer themselves. In reviewing a technology’s effectiveness, it is imperative to ensure the data is from impartial, third-party research institutions as well as ASHRAE and/or CDC standards and guidelines.

Why Indoor Air Quality?

The air in an occupied building will normally pass through an HVAC system multiple times per hour depending upon the building type and design. This means that the air we breathe as building occupants will be re-conditioned and re-circulated frequently by the HVAC system, and this includes all air particulates, both desirable and un-desirable. This recirculated air has been exposed to all conditions in the building, whether it be volatile organic compounds (VOCs) directly from a manufacturing process or direct output from building occupants in the form of carbon dioxide. Additionally, any airborne particulates carried by a person can be safely assumed to be part of the recirculated air. When evaluating indoor air quality and determining a plan of action with respect to HVAC systems, these compounds and particulates should be considered. While specific airborne pathogens or other microorganisms may often be the most news-worthy concern, the negative impacts of other airborne contaminants in the airstream is significant and detrimental to both a building occupant’s health as well as their cognitive function¹. Therefore, having an air quality strategy directly related to a building’s HVAC system or design is extremely important so that the ability for a technology or strategy to control or remove these other airborne contaminants is not overlooked.

¹ Environmental Health Perspectives Research

Details by Strategy

Ultraviolet Germicidal Lights

• Technology Overview
• Effectiveness & Benefits
• Concerns & Drawbacks
• Anticipated Costs
• Conclusion

Air Ionization

• Technology Overview
• Effectiveness & Benefits
• Concerns & Drawbacks
• Anticipated Costs
• Conclusion

High Filtration

• Technology Overview
• Effectiveness & Benefits
• Concerns & Drawbacks
• Anticipated Costs
• Conclusion

High Ventilation

• Technology Overview
• Effectiveness & Benefits
• Concerns & Drawbacks
• Anticipated Costs
• Conclusion