“Air Changes Per Hour” and other things you should know about air quality and ventilation

The airborne elements of the coronavirus COVID-19 have made everyone sit up and pay attention to indoor air quality—and that’s a good thing, given that poor air quality not only contributes to the spread of disease, but has also been proven to dull the senses and decrease productivity in workplaces.

So, more people are focusing on air, circulation and ventilation systems. In fact, health professionals advocate increasing ventilation in buildings to improve air quality—but it isn’t as simple as it sounds. For one thing, many modern buildings are designed to keep air in for energy efficiency, with windows that aren’t operable. And, just turning up the AC won’t do the trick. In fact, some ventilation systems aren’t designed to bring in fresh air; instead, they just recirculate the air that’s already present. It can be confusing. Here’s a primer:

Air Changes per Hour

Air Changes Per Hour (ACPH) is king

Air changes per hour is the rate in which indoor air in an enclosed space is completely recycled, making for fresher, cleaner air. The higher the rate, the more complete changes of air occur. That’s important since viruses and germs tend to linger in the air; COIVD-19 has been proven by researchers to be transmitted via aerosolization of infected droplets (from coughing, sneezing and the like).

While there isn’t a standard for preferred air exchanges per hour, some health care professionals suggest a good ventilation system will exchange the air at least three times an hour, while exceptional systems will exchange the air in an enclosed space five times per hour or more. To give you some perspective, a home with one window open can expect roughly one air change per hour.

To learn how to calculate the air changes per hour, try this handy calculator.

Ventilation systems can play a role

HVAC systems can impact the air quality. For example, clean air filters can positively affect airflow, making ventilation systems work more efficiently. And, properly sized filters can help capture dust, dander and some germs. So, ensuring that ventilating systems are in top working order can help.

Air Changes per Hour

Air purifiers can boost Air Changes Per Hour

Some ventilation systems inside buildings are designed for energy efficiency and aren’t all that great at increasing air exchanges. What’s more, older systems can’t adequately handle the demands of increased workload.

So, consider augmenting ventilation systems with standalone air purification systems. For example, commercial-grade AeraMax Professional air purifiers are designed to scrub the air, using a unique four-stage HEPA filtration system to remove up to 99.97 percent of airborne contaminants—like viruses, germs, flu, bacteria, dust and odors—from enclosed spaces.

What’s more, AeraMax Professional air purifiers can perform five air exchanges per hour on their own, when placed in an appropriately sized room; there are different AeraMax Professional models designed to work in different sized rooms, based on square footage. The five air exchanges mean the indoor air is replaced five times an hour, giving occupants cleaner, fresher air.