COVID-19 and Air Filters
COVID-19 can be contracted through commonly touched surfaces, but the virus can also be transmitted through airborne particles and droplets. Even particles that have settled onto surfaces can become airborne if disturbed. As we approach colder daily temperatures, you may spend more time indoors with others. An increased volume of indoor traffic can lead to higher levels of airborne droplets. The HVAC system in your home or office can circulate contaminated air. Without a proper air filter, HVAC units cannot catch airborne droplets of the virus. Instead, your unit may be forcing virus droplets throughout the building.
MERV, or Minimum Efficiency Reporting Value, is a rating system that categorizes how well a filter can remove particles from the air. As the MERV rating increases, the particle size decreases. For example, Lower MERV ratings can remove larger particles from the air like dust, allergens, mold, pet dander and more. Higher rated MERV filters can trap smaller particles like viruses, odors, and airborne chemicals. The increased ability to catch particles results in decreased air flow. Verify that the system is equipped to handle high MERV filters before installing.
Before the COVID-19 pandemic began, the only facilities that used MERV 13 filters were industrial and medical environments. These have always been areas where thorough air filtration is essential. Since the onset of the pandemic, the CDC recommended that large indoor spaces update their HVAC systems with MERV 13 filters or higher. The national need for high MERV filters created a spike in demand. Even now, the operational status of offices and schools depends on whether they can acquire the needed equipment for proper air filtration.
The material used in air filters, called media, has experienced an extreme shortage. The high MERV media can catch airborne droplets of the virus, making it a useful material for mask production. Much of the media that is normally used for filters has been sold to companies who are producing masks and respirators for hospitals. The increased demand for filters combined with mask production resulted in many companies experiencing a backorder on product. The backorder has hindered companies’ ability to fulfill their orders on time.
AIR FILTER SUGGESTIONS
As recommended by the ASHRAE (American Society for Heating, Refrigerating, and Air Conditioning Engineers), air filters rated MERV 13 or higher should be used in HVAC systems. Double check that your unit can handle a high-rated MERV filter before installing, as MERV 13 and higher air filters restrict airflow. If your unit cannot support MERV 13, using a MERV 11 filter may produce similar effects. When possible, circulate outdoor air with indoor air. Keep your filtration system running as much as possible. This will increase air flow and the percentage of airborne particles caught by the filter. Changing the filter on a routine basis will ensure optimal performance from your unit. Change the filter more frequently in high traffic areas.