Indoor Air Quality Considerations (IAQ) During COVID-19

Much has been written about how easily the COVID-19 virus can be transmitted from human to human. This is primarily through close contact and transfer in tiny airborne droplets which can be expelled into the air by a cough, sneeze or in some cases simply by talking and breathing. This issue can be compounded when indoors due to the inherent nature of enclosed space and the limited ability to socially distance in our workplaces.

The two primary levers that we can use to manage the transmission of the virus inside of our buildings are to modify occupant behavior and to improve the indoor environment. This article is focused on ways to improve indoor air quality (IAQ) that every facility team should consider to help to ensure a safe and healthy work environment.

The EPA has recommended that guidance provided by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) for managing IAQ during the current pandemic be followed. ASHRAE has produced statements and guidelines supporting that aerosol transmission of COVID-19 through the air within office environments is possible and can cause a likely risk to occupants if spaces are not conditioned and filtered properly. ASHRAE’s formal statement says that, “Transmission of SARS-CoV-2 through the air is sufficiently likely that airborne exposure to the virus should be controlled. Changes to building operations, including the operation of heating, ventilating, and air-conditioning systems, can reduce airborne exposures.”


Are your facilities ready for occupancy from an Indoor Air Quality (IAQ) standpoint?


Most modern buildings have HVAC systems and controls to manage airflow through space. These systems are charged with properly conditioning the air for occupant comfort and enabling equipment such as computers to function properly. HVAC systems play a critical role in controlling the movement of air and therefore affecting the potential spread of contaminants. To help your organization prepare for a healthy return to the workplace the following aspects should be addressed.



Clean, inspect and replace filters

Air filtration is at the top of the list when it comes to limiting the spread of contaminants. The CDC recommends a MERV rating of 13 at a minimum. MERV stands for Minimum Efficiency Rating Value and is the standard method for classifying filters. However, most older HVAC systems have MERV 11 or even MERV 7, which are too coarse to provide sufficient filtration. Arbitrarily increasing the MERV rating will increase the load on the HVAC system, possibly beyond its design load, and will impose energy penalties. If you have an older HVAC system, you must review the system design before increasing the MERV rating of your filters.

The best HEPA filters are largely recognized to have MERV values between 17-20. These filters have been shown to remove dust, vapors, bacteria, fungi and effectively capture viral particles that may transmit infections. Filters should be replaced and cleaned per manufacturer’s recommendations to remove potential contaminants and blockage that may occur over time.


Increase fresh air volumes

Ventilating your facilities with as much outdoor air as you can is essential to controlling the spread of viruses and diluting airborne contaminants. Many modern air handling systems do allow for the control of the amount of external fresh air that enters your system.

The CDC has recommended the increased use of natural ventilation by stating, “Consider using natural ventilation (i.e., opening windows if possible and safe to do so) to increase outdoor air dilution of indoor air when environmental conditions and building requirements allow.” Since many existing office buildings have fixed windows and external doors such as fire, security and entry doors that need to be properly closed in accordance with local codes, natural ventilation may not be possible.



Manage Temperature and Humidity

Dry cool air may create the highest risk conditions for airborne transfer of COVID-19 in buildings. Research suggests that maintaining an indoor humidity between 40-60% humidity indoors may be ideal to limit the airborne spread of COVID-19. Specific indoor temperature research at this point has been inconclusive except in how it relates to the level of humidity within the space.  Because temperature and humidity are closely linked in terms of occupant comfort a balance must be struck between the two.  Monitoring both as part of your COVID-19 planning and control is recommended to help product the optimal environment to limit transmission.


Conduct daily facility health checks

Conduct daily building health checks to ensure the HVAC system is functioning properly. Ensure exhaust fans and ducts are operational and not blocked, especially in high risk areas such as restroom, break rooms and other areas of congregation. Also, check your filters and IAQ levels with environmental sensors.  In addition, through inspections, ensure that exhaust fans and ducts are operational and not blocked, especially in high risk areas such as restroom, break rooms and other areas of congregation. Daily checks that take Indoor Quality and the health and safety of your facilities and occupants can go a long way in helping you create the best environment for success to manage COVID-19.


Environmental Sensor Analytics


Deploy environmental sensors

IAQ sensors can help you understand the environmental conditions within specific areas of your facilities. FM:Systems Environmental Fusion Sensors combined with FM:Systems Analytics provide an unparalleled ability to monitor and measure IAQ simultaneously with real-time occupancy sensing, all in an industry leading single sensor and analytics solution. Values for humidity, temperature, CO2, equivalent VOCs, light levels, sound and occupancy parameters can be displayed in charts and on a heat map, giving full visibility into environmental quality for each space and how relates to occupancy levels. The FM:Systems environmental fusion sensors can be used to manage occupancy levels by monitoring congestion on a given floor or area within a building and alerting end users when their specifically defined thresholds for each parameter are exceeded. These features with combined sensors enables FM:Systems to deliver a powerful solution that helps our clients deliver healthier, safer high performance buildings to their occupants.


Download our E-Book In the Future Workplace, We Will Prioritize People over Place to learn how to retool your organization with employee-centric performance indicators like Indoor Air Quality to ensure a safe workplace.