By Aleks Sheynkman
Director of Engineering
As the novel coronavirus (COVID-19) marches on, there’s increased focus on how it spreads. Studies show respiratory droplets as the most common method of transmission; however, a new study from April indicates the virus can survive on airborne particles for an indeterminate period of time. This new revelation warrants action by facilities managers—particularly when it comes to developing a COVID-19 workplace HVAC checklist.
If COVID-19 can survive in an airborne capacity for any length of time, facilities managers face the arduous task of addressing recirculated airflow quality. Failure to institute HVAC safety measures could mean broad workplace exposure to the virus.
Control HVAC to control exposure
There’s significant evidence that repeated exposure plays a role in the severity of COVID-19 cases. The infectious dose of COVID-19 is unknown, but it’s speculated that repeated exposure boosts viral load and speeds the virus’ ability to propagate in the body. In simpler terms: more exposure leads to a worse infection.
If coronavirus particles can survive airborne as part of a building’s forced air system, it could mean repeated exposure for employees every time an HVAC system kicks on. Those particles will continue to circulate until they’re removed from the system. Thankfully, there are ways to both remove them from circulation and prevent them from entering it altogether.
1. HVAC cleaning and maintenance
A thorough inspection of your building’s forced air system is a good place to start. Dust, lint, allergens, mold, dirt, and an assortment of other debris eventually come to rest in ducts if they’re not trapped by a filter. An inspection that yields evidence of these can signal the need for cleaning.
Whether dirty or not, commercial duct cleaning can provide some peace of mind in the current climate. Duct cleaning involves covering all forced air registers and blowing or sucking debris to these areas, where it’s vacuumed out. For most facility managers, duct cleaning isn’t a novel concept—it’s recommended once every year or two.
Alongside duct cleaning, work with an HVAC contractor on routine and general maintenance. Replace filters, repair damaged ducting, and check electrical and thermostat components to ensure the building’s system is efficient and functional.
2. Increase air filtration capabilities
Once the system is clean, consider the level of air filtration it’s capable of. This requires knowledge of Minimum Efficiency Reporting Value (MERV) ratings and different filter types.
Most commercial systems have filtering capabilities up to MERV ratings of 11-13, considered good to superior. MERV ratings go up to 16, but not every commercial system will need that level. Instead, consider the type of filter to improve indoor air quality and safety. The most common options include:
- Fiberglass filters. Layered fiberglass and metal frames offer excellent stoppage for larger materials in recirculated airflows. They have moderate resistance to airflow, good for maintaining system efficiency.
- Polyester and pleated filters. These are disposable filters replaced monthly or quarterly, great for trapping dust. They have a high resistance to airflow, which may lower system efficiency.
- High Efficiency Particulate Air (HEPA) filters. These units filter air at a fine scale, to trap 99.97% of particles 0.3 microns or larger. They’re the superior option for filtration at-scale.
Right now, it’s smart to consult an HVAC professional about HEPA filters if you don’t already use them. HEPA filters will remove any trace of airborne particles for cleaner air, instantly reducing the threat of airborne coronavirus particles.
3. Monitor cycling for air exchange rates
With a clean system and enhanced filtration, the workplace and everyone in it will benefit from improved air quality. For facility managers who want to take it one step further, consider tracking HVAC cycle rates. This will show how often the forced air system kicks on and how long it runs. Not only is this a great way to gauge system efficiency, it’s a good quality control measure as you track air quality.
The best way to monitor HVAC cycle rates is through an Internet of Things (IoT) enabled sensor or a smart thermostat. Collect cycle data over a week or two, to gauge efficiency and stay up-to-date on the building’s forced air system’s performance.
Reduce the risk of exposure for employees
Airflow is integral to workplace comfort and employee health. It’s good practice to maintain an efficient, clean forced air system—even more so if coronavirus can indeed survive airborne. Facility managers should take extra steps to evaluate and maintain the building’s forced air system, clean and filter air where possible, and monitor exchange rates to maintain safe, clean air throughout the work environment.
There’s still much to learn about how COVID-19 spreads and what safety measures prevent transmission. Until we know for certain, the best we can do is be proactive. A COVID-19 workplace HVAC checklist is one example.
Keep Reading: Top Coronavirus Workplace Resources