What’s the Difference between MERV, MPR and FPR?

Air filters are an essential part of your HVAC system, and you may have encountered these ratings when shopping for them. Air filters can improve indoor air quality and safeguard your HVAC system. Choosing the right air filter rating will help you meet your filtration priorities and achieve the cleanest possible air in your home.

In this blog, we’ll help you understand each of the air filter ratings and why they are important.

Here are the 3 main rating systems you’ll see:

• MERV – Minimum Efficiency Reporting Value Rating
• MPR – Microparticle Performance Rating
• FPR – Filter Performance Rating

What does MERV stand for?

The MERV rating system, established by the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE), is the industry standard for air filter ratings.

What is a MERV Rating?

A MERV rating is designed to let you know exactly what airborne particles a filter can capture. AC filter MERV ratings start at 1 and go up to 16. The higher the rating, the higher the resistance to airflow.

Many systems were not designed to accommodate filters higher than MERV 8, as the airflow would be too restricted. This can result in coil freeze-up, flooding, or compressor failure.

What are the different MERV ratings, and what do they filter?

The MERV rating lets you understand precisely what contaminants your filter can reduce. Here’s a quick rundown of the different MERV rating ranges.

MERV 1-4: Minimum Filtration, Maximum Air Flow

This MERV will capture larger airborne allergens like pollen and dust mites, but that’s about it. This type of filter is ideal for situations where airflow is the priority, not filtration.

MERV 5-8: Fair Filtration, Adiquate Air Flow

This filter will ensnare dust mites, pollen, and the most common household contaminants, including carpet fibers and hair. MERV 8 filters are rated to filter aerosols like hair spray, auto emissions, and even mold spores. These filters are ideal for most households as they offer adequate filtration without restricting airflow.

MERV 9-12: Protects Against Allergens, Limits Air Flow

Here’s where filtration becomes the priority. This MERV rating range will eliminate the finer allergens in the air, including lung-damaging dust, smog, pet dander, and tobacco smoke. If you or someone in your household has allergies or respiratory issues, you’ll want to use MERV in this range. However, it’s important to note these MERV ratings can impact airflow.

MERV 13-16: Top Level Filtration, Restrictive Air Flow

The lowest possible MERV recommended for residential applications is MERV 13. This will prevent bacteria and virus carriers from circulating in your home’s air but will limit airflow significantly. You should only use this type of MERV rating if you are concerned about these contaminants in your home, or your system requires them.

Anything above a MERV 13 is only recommended for medical or industrial facilities. Installing anything above a MERV 13 in your furnace or HVAC can damage your system.

Here’s a MERV rating chart to help you better understand their effectiveness:

Filters Fast® Brand air filters are available in MERV 8 and up and are tested to ensure they meet the MERV rating standard.

Shop Filters Fast® Filters

Why is airflow important?

When figuring out what air filter rating you need, you’ll need to consider airflow.

Airflow has a direct impact on whether your filter can do its job. If airflow is too low, this can prevent the air filter from pulling contaminants into the filter. If the airflow is too high, contaminants can skip the filter. This can lead to bad air quality or harm your HVAC system.

What does an MPR rating on air filters stand for?

MPR, or Micro particle Performance Rating, was developed by 3M, which makes Filtrete Air Filters. MPR Ratings range from 100 to 2800, indicating the filter’s capacity to remove particles from 0.3 to 1 micron.

MERV vs MPR

If you’re interested in the Filtrete brand for air filters, you’ll want to ensure you understand the MPR ratings. Here’s a quick look at how they compare to MERV ratings.

• 800 MPR, 1000 MPR, 1085 MPR & 1200 MPR is similar to a MERV 11 rating
• 1500 MPR & 1550 MPR closest to a MERV 12-rated filter
• 1900 MPR & 2200 MPR will offer MERV 13-level filtration
• 2800 MPR will provide MERV 14 air filtration

Shop 3M Filtrete Air Filters

FPR Air Filter Ratings

FPR, also known as Filter Performance Rating, was created by Home Depot for the brands sold in its stores. Similar to MERV ratings, this system ranges from 4 to 10.

According to The Home Depot, a simple way to remember what FPR numbers are: the higher the number, the better the air filter’s performance.

How do FPR filter ratings compare to MERV & MRP ratings?

• FPR 4-5 would be considered a MERV 8 or MPR 600, which captures common airborne contaminants.
• FPR 6-7 is close to MERV 9-12 and MPR 1000-1200, giving you more filtering capabilities with limited airflow.
• FPR 8-9 is equal to a MERV 12+ or MPR 1500+ rating. This rating provides the best possible air quality with more restricted airflow.
• FPR 10 is the best rating and will remove odor-causing particles and airborne contaminants.
  Here’s a simple chart we put together to explain each of the different air filter ratings and what the differences are:

When in doubt, consult your HVAC unit manufacturer’s data to determine the correct MERV rating for your filter.

Finding Your Filter: Factors to Consider

In addition to considering the contaminants you want to reduce in your home’s air, you’ll also need to consider where you live, the health needs of your household, and your budget.

What is the weather like where you live? You should take this into account when choosing which rating to use in your home. For example, if summer’s hot and humid, you should opt for a lower MERV. MPR or FPR so that airflow is maximized. Doing so can help keep your home cool and beat the heat.

How many people live in your home, and what are their health needs? If you or a family member experience seasonal allergies, you’ll want to choose a rating that can trap common irritants like pollen, dust, and mold spores. In addition to people in your home, if you have pets, you’ll want to ensure that your rating is rated to catch pet dander.

Do you have a budget? Choosing a higher rating will come with a high price tag, so you’ll want to ensure that the cost of these filters fits within your budget. Filters should be changed every 1-3 months, so you’ll need to plan to have this expense recurred a few times a year.

Reminder to Replace

Once you’ve chosen the correct filter rating, you’ll want to change your filters regularly to keep your HVAC in good condition. It is recommended that 1-inch air filters be changed every 1-3 months. This helps ensure your filter is not overloaded with contaminants and impedes airflow.

Replacing your filters regularly can benefit greatly, including improved system efficiency, lower energy bills, emergency repair prevention, and prolonged system lifespan.

There are several ways to keep track of changing your filter: You can set a reminder on your phone, buy air filters in bulk so you have them on hand, sign up for a filter subscription service, or change your filters when the seasons change. Whatever you choose, ensuring you replace your filter every so often is key.

Don’t Forget About HVAC Maintenance

In addition to replacing your filters regularly, having your HVAC routinely serviced by an HVAC professional will help keep your system in good working order. HVAC companies near you should offer seasonal service where they check your system to ensure everything works properly. It’s best to schedule this maintenance in the spring and fall to ensure your system is ready to handle the heat or the cold.

Consider this, paying a few hundred bucks twice a year to have your HVAC serviced can help prevent shelling out thousands of dollars to repair or replace your system.

Now that you know what the rating systems mean and how they relate to you, we hope you have the information to make the best filtration choice. If you still need additional assistance with choosing the proper rating for your air filter, we’re happy to help. Call us at 866-438-3458 or email us at [email protected].

Want more information about air filter ratings? Check out these blogs:

• An In-Depth MERV Ratings Guide: Must-Read Before You Buy
• What does MERV mean?
• Which MERV Rating Should I Choose?
• Difference Between MERV Ratings – MERV 11 Recommended 
• Which Air Filter MERV Rating is Recommended for Allergies?