What You Need to Know About Choosing an Air Filter

October 21, 2020

Most Americans spend at least 90% of their time indoors. You may be surprised to learn that the air in your Nacogdoches, TX, home is up to five times more polluted than the outdoor air. As cooler weather arrives, you may also be concerned about the spread of bacteria and viruses through the air of your home. Air filters play a big role in removing particles and biological materials from your home’s air, and not all air filters are created equal. Read on to learn about air filters and how to choose the right one to improve your home’s indoor quality.

Air Filter Materials

Air filters are available in a range of materials, including fiberglass, polyester, and synthetic self-charged fibers. Fiberglass filters are inexpensive and disposable. They capture large particles and facilitate maximum airflow. Polyester fibers offer medium-range filtration from contaminants. They cost about four times more than fiberglass air filters. A polyester air filter is also disposable. Synthetic self-charged air filters are washable. They capture the medium and large particles from your home’s air. They last longer but require regular cleaning. High-efficiency particulate air (HEPA) filters are the most expensive and capture tiny particles, including viruses. However, they reduce airflow and can decrease heating and cooling system efficiency.

Types of Air Filters

There are two types of air filters. Pleated air filters have media that is folded into pleats. The pleats provide more surface area or the media to capture tiny particles. The pleated filters are more efficient than flat filters. They can be made of polyester or synthetic materials. The pleated filters also have a long lifespan of about three months. They capture particles as small as 0.3 microns in size. Non-pleated air filters capture some medium and most large particles. They’re low cost and maximize airflow.

How Air Filters Are Rated

Air filters for heating, ventilation, and air conditioning systems are rated with the minimum efficiency reported value (MERV) rating system. MERV ratings range from one to 20. For each one-unit increase in the MERV rating, the filter captures about 10% more airborne contaminants. Each one-unit increase in the MERV rating also allows the filter to capture smaller particles.

For a home where nobody has breathing problems, a MERV five to eight rating is acceptable. If anyone in your household has asthma, allergies, breathing problems, or heart disease, it’s wise to choose a higher MERV rating for your air filter. Hospitals use ventilation systems with MERV 16 air filters. These are also known as high-efficiency particulate air (HEPA) filters. These air filters reduce airflow but capture almost every particle, including more than 99.9% of viruses.

Particles Captured by Each Type of Air Filter

A MERV five filter captures hair, spores, dust mites, cat and dog dander, cement dust, hair spray, and pudding mix particles. These are large particles that could irritate a healthy person’s respiratory system. A MERV nine filter captures lead dust, flour, auto fumes, and cooking oil droplets. MERV 13 filters capture bacteria, tobacco smoke, and respiratory droplets from sneezes and coughs. MERV 16 filters trap carbon dust and viruses that are 0.3 microns or smaller in size.

Why You Should Choose a High-Rated MERV Air Filter

If you or another member of your household has a breathing disorder or heart disease, breathing in small particles could worsen your symptoms. A high MERV-rated filter removes almost all of those particles. You may be able to breathe easier and experience fewer symptoms of your condition. If a person in your home has a respiratory infection, such as influenza or COVID-19, a high-rated MERV filter removes most of the viruses they cough or sneeze into the air. This lowers your chance of getting sick.

When to Change Your Air Filter

Even if you buy the highest-rated filter that works in your heating and air conditioning system, it won’t help you if it’s dirty. A dirty air filter won’t capture any particles. The clogged filter also reduces your heating and cooling system’s efficiency. Check your filter monthly, and change it when it’s visibly dirty or at least every three months.

Nacogdoches Sheet Metal, Plumbing & Air Conditioning, LTD. is your trusted source of quality air filters and other indoor air quality solutions in Nacogdoches. We’re also prepared to provide you with cost-effective sheet metal fabrication, plumbing and heating, and air conditioning maintenance, repair, replacement, and installation services. For additional information about air filters and how they affect indoor air quality, contact us at Nacogdoches Sheet Metal, Plumbing & Air Conditioning, LTD. today.