Did you know that average person spends 90% of their time in indoor spaces? This is also where concentrations of pollutants are 2-5 times greater as compared to the outdoor levels. As more of us are under a stay-at-home order to help stop the spread of the Coronavirus, the amount of time spent indoors is increasing, making indoor air quality in the home more important than ever. Our focus has shifted to ensuring we’re taking the necessary precautions needed to protect our families and reduce the chances of coming into contact with the virus. However, it is important to remember that the Coronavirus is not the only virus, germ, disease or pollutant we need to protect ourselves from in our home.
Coronavirus: Particle Size and Spread
It is believed that the Coronavirus is spread mainly by respiratory droplets that can travel several feet from the person that is infected when they cough or sneeze. Covering your mouth when coughing or sneezing is the first thing you can do to help control the spread. It is also the reasoning behind the recommendation to wear a face mask while out in public. The virus has the same traits as other viruses like a sore throat, common cold and flu, by how it spreads from person to person.
According to the American Lung Association, airborne particles 2.5 microns or less (called fine particles) are considered an inhalation hazard as they can be “easily inhaled deeply into the lungs where they can be absorbed into the bloodstream or remain embedded for long periods of time.” A respiratory droplet is approximately 1 micron in size. A micron (or micrometer) is a unit of measurement that is one-millionth of a meter. To put that into perspective, the average human hair is approximately 50 microns. The human eye is only able to see particles that are at least 5 microns in size. 98% of all the particles floating around in our indoor air are </= 1 micron in size, including the coronavirus.
Will HVAC Filters Capture These Small Coronavirus Particles?
HVAC filters come with a micron rating representing an air filters effectiveness in removing particles of specific sizes. Standard air filters found in most HVAC systems are designed to capture particles that are 5-10 microns or larger. So, if a filter has a micron rating of 7, it is able to trap particles that are 7 microns and larger. That sounds shocking after learning the micron size of the Coronavirus, doesn’t it? However, there is still another level of understanding when it comes to an air filter’s effectiveness in removing particles of specific sizes. Here are two important terms:
- Nominal Micron Rating: This rating measures how efficient an air filter is at capturing airborne particles of a certain size, ranging from 50-98.6%. It tells you the smallest size particle that may get trapped. For instance, if you have an air filter that removes particles as small as 8 microns with a 50% nominal micron rating, then the filter will capture around 50% of airborne particulates 10 microns in size.
- Absolute Micron Rating: This rating gives the size of the largest particle that will pass through the filter and means that the filter is capable of removing at least 98.7% of a specific size particle. It basically tells you the filter is able to better remove particulates of the specific micron size. If your current home air filter has a micron rating of 5, it is leaving a great majority (98%) of indoor air pollution floating around your home.
Now that you have all the information on microns, it’s clear you need an air filter captures airborne particles smaller than 1 micron. But do they exist? On to the last thing you need to know about protecting your indoor air with the right air filters: MERV ratings.
MERV stands for Minimum Efficiently Reporting Value. It is a numeric value that tells you the effectiveness of your selected air filter. MERV ratings are calculated by measuring the number of particles a filter can trap compared to the number the particles it’s trying to filter. This means that if there are two filters in the same room, the one with the lower MERV rating traps fewer particles. The range for standard MERV values is typically from 1 to 16 for home HVAC systems, with the number indicating how well the filter removes particles from the air. The higher the MERV number, the better the filtration.
MERV 1-4: Common standard filters. Basic filtration. Low cost.
MERV 6-8: Good filtration usually used in residential settings. Made of pleated paper or cloth.
MERV 9-12: Relatively high efficiency, middle of the road filters. Can trap particles of 1 micron or larger.
MERV 13-16: Highest efficiency, best standard filters available. Can trap particles as tiny as 0.3 microns or larger.
There are filters available with MERV ratings higher than 16; however, they are thick and dense, and a typical residential HVAC system cannot readily handle them. In fact, they can end up interfering with the airflow by restricting it. This could end up reducing the effectiveness of your heating and cooling system and result in HVAC equipment damage. If you want an air filter with a MERV rating higher than 16, you must make sure that your HVAC system can handle them before buying and installing one.
What You Can Do to Protect Your Indoor Air
- Cover your mouth with your elbow (NOT YOUR HANDS) when you cough or sneeze.
- Wear something over your mouth when in public spaces (mask, scarf, or a bandanna).
- Get fresh air circulating throughout your house. Open doors and windows as much as possible. Higher ventilation is key in reducing the risk of viruses.
- Consider removing shoes before coming in the house. Shoes carry in dirt and particles that can be kicked up into your indoor air.
- Get outside as much as possible, keeping a safe distance (6 feet or more) from anyone other than your immediate family.
- Monitor your indoor humidity level as viruses survive longer in lower humidity. For more information on humidity levels, click here.
Most importantly, check your air filters and change them regularly. If they are dirty, they need to be changed with a fresh clean air filter. How do you know if your air filter is dirty? When removing the air filter from the handler, hold it up to a light source and you will be able to see if the filter is dirty or clogged – if you can’t see the light through the filter, then it’s definitely time for it to be changed. Dirty, clogged air filters can’t do their job of trapping viruses like the coronavirus and other indoor air pollutants!
US Home Filter is Here for YOU
In times like these, emotions are running high and there is fear and concern about the unknown. Most of us probably feel like we need to become experts on things we never imagined having to think about. If you have ANY questions regarding your filter size or choosing the MERV rating that is best for you, don’t fret. For personal assistance with your air filter needs, please contact us now online or call us at (855) 237-1673 and we will do our very best to assist you in selecting the right filter for your individual needs. You can also take a look at our air filter measurement guide to help you pick the right size or call us and we can easily assist you with ordering the exact air filter size you need and recommend the best rating for you depending on the level of filtration you want. Whether you need AC or furnace filters, a specialty Whole House filter, a Grille filter, or even a custom air filter size, we have a professional and helpful staff ready to take care of you! We want to earn your business and we guarantee your satisfaction! Take advantage of our quality products, vast selection, low prices, and enjoy FREE SHIPPING on every air filter order within the Contiguous USA.