Since 2020, many of us have had to take on the responsibility of ensuring good Indoor Air Quality (IAQ) in our homes and places of work whether we knew what that meant or not! The urgency of protecting those in our care drove us to take some form of initial action with little guidance.On March 29th 2022, the White House held a conference launching the Clean Air in Buildings Challenge.It identified air borne aerosols as the primary method of transmission of the SARs-COV-2 virus and issued a “call to action” to those responsible for building maintenance.They focused on three areas: Ventilation, Air Filtration, and Air Disinfection.While this guidance is long overdue, a sustainable strategy begins by understanding how each of these categories function.
[caption id="attachment_225116" align="alignright" width="285"] Franchise Owner Nicole Walsh[/caption]
Ventilation refers to bringing fresh air into a room. The term “air exchange” refers to bringing in a volume of air equal to what was in the room while venting out the same volume of air.We rate this speed in how many times this exchange is done per hour. The average home exchanges at a rate of 0.35 times per hour.School buildings average 1.5 times per hour while newer office buildings exchange at a rate of 6 changes per hour.
This process, while vital, is commonly misunderstood.The air being exchanged is not fully replacing the contaminated air, but rather mixing the new fresh air creating a diluted mixture. The White House’s recommendations suggest improving ventilation to ensure 6 changes per hour.At that rate however, it would take 46-69 minutes to eliminate airborne contaminants from a single exposure, far too long to prevent transmission of the virus.
Air Filtration refers to removing particulate (air debris) from the air.This is done by catching the particles in a filter.HEPA filtration is ideal for mitigating in-room risk.This can be done with portable units or with an appropriate appliance installed in the ventilation system.
The initial guidance we all received was to increase the prefilter in our ventilation system to MERV 13.This was never meant to be a long-term solution.The pre filter on your HVAC was intended to protect the HVAC, not people.The MERV Rating refers to how hard your air handler must work to pull air through.Switching from MERV 8 to MERV 13 creates a 300% increase in the energy consumption of the air handler. Our ventilation systems already account for 44% of a building’s energy consumption.The dramatic increase in energy demands the MERV 13 filters place is not sustainable.For companies mindful of their ESG rating (Environmental, Social and Governance risk), this needs to be addressed.
Air Disinfection systems are the 21st century technology approach to improved IAQ.Technologies such as ActivePure, safely disinfect air and surfaces in a room continuously providing 10 times the protection of increased air exchanges or filtration for 1/10th the cost.That’s equivalent to more than 104 air exchanges per hour.When choosing a solution, check to see if the testing has been validated by the FDA.
The Environmental Health Consultants at Aerus provide free site evaluations and can help review your IAQ strategies for efficacy and sustainability.