The Importance of Proper Air Filtration

Oftentimes we are more concerned about outside air quality and pollution, but did you know that indoor air can be 25 times more polluted? We spend nearly 90% of our day inside, it should come as no surprise then that the air quality in our homes, offices and other places of business be as free of air pollutants as possible.

What is air filtration?

Air filtration refers to the removing of airborne particles using media filters. From a high level, air filtration is providing in a heating, ventilation, and air conditioning system. There are two main reasons why this is done. (1) to protect equipment components from accumulating dirt/debris. And (2) to reduce the quantity of air contaminants inside the building environment.

Air filters work by capturing a portion of the particles in the air that passes through the filter. This basic concept holds true for air filtration systems however, the mechanism used to capture the particles and the quantity and/or size of the particles captured will vary depending on the filter that is used.

What are air contaminants?

Chapter 11 of the 2017 ASHRAE Handbook: Fundamentals define air contaminants as either being particles, gases, or vapors. Gases and vapors exist in the air as individual molecules, whereas particles are larger than individual molecules. Due to their relatively small size gases and vapors are not typically removed from the air through traditional media filtration. For the sake of brevity these forms of air contaminants will not be discussed. This article will focus on airborne particles i.e., particles that are composed of solids, liquids, or a combination of the two.

What are air borne particles?

Air borne particles can consist of many different materials. These particles can either be produced inside or outside of a building. Outdoor particles may be produced from natural processes (such as wind, volcanic activity, or the decay of organic materials) or human activities (like construction, agriculture, or industrial plants). Particles produced inside a building can come from the building’s occupants, building activities or material off-gasing. Airborne particles can be broken up into the following groups:

1. Dust, fumes, and smokes,
2. Mists, fogs, and smog,
3. Bioaerosols (i.e., viruses, bacteria, mold spores, allergens, dander, and endotoxins).

Why is proper filtration important?

Poor indoor air quality can be detrimental to our health. The elderly, children, or those with allergies or compromised immune system are the most susceptible groups. The negative effects can include dizziness, breathing problems, sinus issues, flu, and viral infections. Household contaminants like pet dander, mold spores, pollen and bacteria are unavoidable. However, diligent cleaning will help to minimize these contaminants, but the best way to be healthy and safe is having a good air filtration and purification system.

Air cleaners and HVAC filters are designed to filter pollutants or contaminants out of air that passes through them. Air cleaning and filtration can help reduce airborne contaminants, including particles containing viruses.

Air cleaners, HVAC Filters, and COVID-19

When effectively use, air cleaners and HVAC filters can help reduce airborne contaminants including viruses in a building or a small space. However, by itself, air cleaning or filtration, is not enough to protect people from exposure to the virus that causes COVID-19. But along with using these items and the best practices recommended from the CDC and others, filtration can be part of a plan to reduce the potential for airborne transmission of COVID-19 indoors.

Within a school, office, or commercial building setting, upgrades to the current HVAC filters may be appropriate for your specific building and HVAC system. However, consult with an HVAC professional before performing this task yourself. The variety and complexity of HVAC systems in large buildings requires professional interpretation of technical guidelines, such as those provided by ASHRAE and CDC. EPA, ASHRAE, and CDC recommend upgrading air filters to the highest efficiency possible that is compatible with the system and checking filter fit to minimize filter air bypass.

In conclusion

Regular household or building cleaning is beneficial. However, to rid the air of pollutants an air purifier system is needed. An air filtration system can substantially decrease airborne particles that is indoors. This is essential since most of our time is spent inside – 90% of our day in fact – and the air inside a building is 25 times more likely to be polluted. However, to truly benefit from an air filtration system, filters should be replaced within the 3-to-6-month time frame. As well as performing general maintenance on the HVAC system. These steps will ensure the systems longevity and efficiency.