A case study in an east coast university from air filtration industry leader, Camfil, highlights the importance of MERV-A rated air filters.
Earlier this month, the Centers for Disease Control and Prevention (CDC) loosened their masking guidelines, recommending that vaccinated individuals no longer need to wear masks or physically distance themselves from one another in public spaces.
“Essentially, a mask is a final filter. It’s the last line of defense between what’s in the air around you and what goes in your lungs,” says Mark Davidson, Camfil’s Manager of Marketing and Technical Materials, “Now that the mask may be gone, the next line of defense, practically speaking, becomes the facility manager at whatever building you happen to find yourself in.”
In a new video, Allen Oakes, Branch Manager for Camfil’s Birmingham, Alabama, location, explains what facility managers can do to effectively protect building inhabitants, pointing to a recent case study from an east coast university.
ASHRAE (the American Society of Heating, Refrigeration and Air-Conditioning Engineers) has recommended filters with an efficiency rating of MERV13 or higher to best protect public building inhabitants from virus transmission risks. Some jurisdictions even mandated this filter efficiency before public buildings were permitted to reopen.
However, not all MERV13 rated filters maintain that efficiency throughout their lifetimes. ASHRAE also designates some filters as MERV-A, which means they underwent additional testing showing that their rated efficiency will last throughout their lifetime. (Mr. Oakes provides a detailed explanation of what MERV and MERV-A ratings mean in the new video.)
“We find that MERV13 filters tend to drop to the equivalent of a MERV 9 or even as low as a MERV 8 efficiency when their charge dissipates,” Mr. Oakes notes. Effectiveness can deplete in as little as a month or less, depending on the volume of air being filtered and the dirt load accumulated.
The university in the case study had many single-stage air handling units which only had the capability to hold 2″ deep pleated filters which are typically MERV 13 and not MERV 13A filters. Because they would lose efficiency fairly quickly to as little as a MERV 8, the university made the choice to upgrade to Camfil’s 30/30 Dual 9 air filter, a MERV9-A rated filter, in the single-stage air handling units, and supplement this filtration with Camfil’s City M in-room air cleaner in classrooms, dorms, and hallways for additional true HEPA filtration.
Each public building has different needs, which should be evaluated by a professional with experience in virus filtration. Recommending different filter styles over the phone in order to achieve a MERV 13 efficiency carries a certain level of risks. Mr. Oakes adds, “My advice is if you plan on upgrading, make sure you involve a qualified HVAC professional that can help answer these questions to make sure you don’t cause harm to your system or your space.”
About Camfil Clean Air Solutions
For more than half a century, Camfil has been helping people breathe cleaner air. As a leading manufacturer of premium clean air solutions, we provide commercial and industrial systems for air filtration and air pollution control that improve worker and equipment productivity, minimize energy use, and benefit human health and the environment. We firmly believe that the best solutions for our customers are the best solutions for our planet, too. That’s why every step of the way – from design to delivery and across the product life cycle – we consider the impact of what we do on people and on the world around us. Through a fresh approach to problem-solving, innovative design, precise process control, and a strong customer focus we aim to conserve more, use less and find better ways – so we can all breathe easier.
The Camfil Group is headquartered in Stockholm, Sweden, and has 33 manufacturing sites, six R&D centers, local sales offices in 30 countries, and about 4,800 employees and growing. We proudly serve and support customers in a wide variety of industries and in communities across the world. To discover how Camfil USA can help you to protect people, processes and the environment, visit us at www.camfil.us/
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