MERV Air Filter Rating Guide
Which Household Air Filter Rating Should I Use?
There are multiple types of furnace filters with a range of MERV ratings, and it can be difficult to find the one that best fits your needs. Service Experts Heating, Air Conditioning & Plumbing offers free consultations to help you arrive at smart decisions that make you feel right at home.
Selecting the right furnace filter is determined by matching indoor air quality with the HVAC system’s capabilities. Choosing filters with the appropriate MERV ratings is important to ensure your indoor air is clean and healthy without overworking your HVAC system.
Call us at (866) 963-7996 to request a free indoor air quality test!
What Exactly is MERV?
MERV stands for Minimum Efficiency Reporting Value, a rating system created by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). MERV ratings signify an air filter’s effectiveness at lowering airborne particles and pollutants, determined by the smallest particle it’s capable of trapping (measured in microns). As filters become better at improving indoor air quality, their MERV rating goes up, ranging from 1 to 20.
This chart, along with our free consultation, can help you decide on the recommended MERV rating for your needs.
MERV Range | Controlled Contaminants | Typical Application | Air Filter Types |
1 – 4 | Pollen, Dust, Spray Paint, Dust Mites, Sanding Dust, Textile & Carpet Fibers | Residential, Window AC Units |
Disposable Electrostatic
|
5 – 8 | Mold Spores, Pet Dander, Hair Spray, Dusting Aids, Fabric Protector, Cement Dust, Pudding Mix | Better Residential, Commercial, Industrial Workplaces |
Pleated Filters
|
9 – 12 | Legionella, Auto Emissions, Lead Dust, Humidifier Dust, Welding Fumes | Superior Residential, Better Commercial, Hospital Labs |
Pleated Filters
|
13 – 16 | Bacteria, Droplet Nuclei (Sneeze), Tobacco Smoke, Insecticide Dust | General Surgery, Hospital Inpatient Care |
Bag Filters Box Filters
|
17 – 20 | Viruses, All Combustion Smoke, Carbon Dust | Cleanrooms, Radioactive & Carcinogenic Materials, Pharmaceutical Manufacturing | HEPA Filters Specialized Filters |
Understanding Other Measurement Systems
Knowing about MERV ratings may not be enough to help you pick the best furnace filter. For example, some big retailers use the filter performance rating (FPR), which goes from 1–10 and is a different scale to measure a filter’s ability to trap particles. You might also see the microparticle performance rating (MPR) system, which ranges from 300 to 2200 and only measures a filter’s effectiveness at capturing the smallest particles on the MERV scale (0.3–1 micron in size).
Always Use the Right MERV Rating for Your System and Needs
Your indoor air quality can be worse than what’s outside. Choosing the right MERV rating for your air filter requires balancing your HVAC system's capabilities with your desired indoor air quality level.
Remember that a higher MERV rating doesn't automatically make a filter better for your system. As MERV ratings increase, airflow decreases, forcing your HVAC system to work harder to circulate air through your home. This added strain can lead to higher energy bills and potential system breakdowns. Always check your HVAC system's manufacturer specifications for maximum MERV rating limits before purchasing a new filter.
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If an air freshener isn’t doing the trick, there may be microbes or contaminants nearby producing the unpleasant odor. They can be resolved with the sanitation properties of a germicidal UV light. They are particularly effective against odor-producing microorganisms.
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Because carbon monoxide is colorless, odorless, and lethal in heavy concentrations, installing carbon monoxide detectors in central locations is the best way to alert you to its presence.
A carbon monoxide detector is like a smoke alarm, monitoring the air and notifying you if carbon monoxide levels are too high. If possible, you should have at least one detector near every bedroom on all floors in your home. Additional detectors can be placed near the kitchen, living areas or near combustion appliances. These detectors are best used in combination with our HVAC maintenance memberships, which keep your unit in good shape and may help you prevent carbon monoxide.
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Prevention is the best place to start. A few safety precautions to take include:
- Don’t let your car idle in the garage. Cars are a significant source of carbon monoxide poisoning, so do not leave yours going in the restricted space of a closed garage. The same is true for gas equipment such as lawnmowers or snowmobiles.
- Don’t use ovens or grills as sources of heat. These appliances are safe when used right but can make carbon monoxide when used for an extended period in small spaces.
- Never operate a gas generator indoors. The fumes will have a much harder time dissipating.
- Have your chimney inspected by a specialist. This ensures chimneys and vents aren’t blocked and are connected appropriately.
- Confirm gas appliances are operating correctly, particularly your heater. You can ensure efficient, safe operation by booking routine furnace maintenance with Service Experts.
If carbon monoxide has been detected, you should immediately vacate the building and alert the fire department and utility provider. If a leak is discovered, you should then contact a trusted HVAC company for repairs.
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Yes. Eliminating carbon monoxide should be a priority because of the danger it poses to your health and well-being. CO gas can be found in any U.S. home or commercial property, making safe ventilation and prevention strategies universally beneficial.
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Initial symptoms such as nausea and fatigue are often mistaken as a result of the flu. But CO gas exposure can progress, potentially leading to confusion, organ damage, or even death. Other symptoms include:
- Headaches
- Dizziness
- Chest pain
- Vomiting
