Understanding Air Filter Ratings: MERV, FPR, and MPR

When maintaining a healthy indoor environment, air filters play a crucial role. They trap dust, pollen, mold, bacteria, and other particles that would otherwise circulate through your home. But with so many different air filter ratings out there—MERV, FPR, and MPR—it can be confusing to know which one you need. Understanding these ratings is key to choosing the right filter for your home and HVAC system. Let’s dive in and see how each of these ratings can impact your air quality.

MERV: Minimum Efficiency Reporting Value

MERV, or Minimum Efficiency Reporting Value, is among the most commonly referenced air filter ratings. Developed by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), MERV measures a filter's effectiveness in trapping airborne particles. The MERV scale ranges from 1 to 16, with a higher number indicating better filtration performance. Air filters with higher MERV capture smaller particles, such as smoke, bacteria, and even pet dander.

A MERV rating of 8 is generally recommended for home use, as it balances efficient filtration and system compatibility. Filters with this rating can trap particles as small as 3 microns in diameter, including common allergens like dust, pollen, and even smoke particles. 

However, filters with very high MERV ratings (12 or above) are often best suited for commercial or hospital environments due to their ability to capture extremely fine particles—this can put undue stress on residential HVAC systems. Now, imagine what these high-performance filters could do for your home. Not only would they remove the tiniest allergens, bacteria, and pollutants, but they could also make your environment significantly cleaner and healthier. The benefits are hard to ignore.

MERV Rating Scale: 

• MERV 1-4: Captures pollen, dust mites, carpet fibers
• MERV 5-8: Captures mold spores, cement dust, dust lint, pet dander
• MERV 9-12: Captures lead dust, auto emissions, humidifier dust
• MERV 13-16: Captures face powder, sneeze particles, tobacco smoke
• MERV 17-20: Captures virus carriers, microscopic allergens, combustion smoke

Why MERV Matters

MERV ratings are important because they directly correlate to how well your filter captures particles in the air. That said, higher MERV ratings are only sometimes better for some homes. Filters with higher ratings restrict airflow more, which can cause HVAC systems to work harder and damage older equipment. Thus, always select a rating that balances both air quality and your system's performance.

FPR: Filter Performance Rating

FPR, or Filter Performance Rating, is a scale developed by The Home Depot to rate the effectiveness of air filters. Unlike MERV, FPR doesn’t follow a universal standard and is specific to certain brands of filters. FPR ratings typically range from 4 to 10, indicating a better ability to filter out particles.

An FPR of 4-5 is usually sufficient for general home use, capturing larger particles like dust, pet hair, and lint. If you’re looking to filter smaller particles such as pollen or mold spores, you may want to opt for a filter with a higher FPR rating—between 7 and 10. While the FPR rating provides some insight, it’s worth noting that it doesn’t give as detailed or comprehensive an analysis as MERV.

FPR Rating Scale

• FPR 4-5: Captures dust, pet dander, and pollen
• FPR 6-7: Captures bacteria, mold spores, smoke, and smog
• FPR 8-9: Captures bacteria, fine dust, smoke, and some allergens
• FPR 10: Captures the tiniest particles, including allergens and viruses
• FPR 12: The highest rating, capturing VOCs and virus particulates

How FPR Compares to MERV

While FPR is a handy rating system, it’s not as widely used or recognized as MERV. The FPR scale is simpler and easier to understand for consumers, but it doesn’t offer as much granularity in terms of particle sizes. For instance, a filter with an FPR rating of 10 may seem like a great choice, but without understanding its actual filtration capabilities, you might end up with an air filter that’s somehow just too restrictive for your system or ineffective at trapping the specific particles you need to remove.

FPR can be a quick and easy way to shop for filters, but if you need more precision—especially if you have specific health concerns like allergies or asthma—it’s a good idea to prioritize MERV ratings.

MPR: Microparticle Performance Rating

MPR, or Microparticle Performance Rating, is another rating system used primarily by 3M. It’s similar to FPR in that it’s a proprietary rating system, but it focuses specifically on a filter’s ability to trap fine particles or microparticles (smaller than 1 micron in size). MPR ranges from 300 to 2200, with higher numbers signifying better filtration of fine particles, such as smoke, dust mites, etc.

While MPR is an effective way to measure a filter’s ability to trap very small particles, it doesn’t consider larger particles or gases, so it isn’t as comprehensive as MERV. Also, like FPR, MPR is brand-specific, so you may be unable to compare MPR ratings across different manufacturers.

MPR Rating Scale: 

• MPR 100-300: Captures lint and dust
• MPR 400-600: Captures mold spores and dust mites
• MPR 1000-19000: Captures pet dander, smog, smoke
• MPR 1500-1900: Captures virus carriers, bacteria, and sneeze and cough particles

How MPR Fits Into the Picture

MPR is most useful when targeting fine particles, which is ideal for people who suffer from respiratory issues or allergies triggered by small particles like dust mites, pet dander, or even smoke. Filters with high MPR ratings (e.g., 1500 to 2200) can capture a more significant % of these particles, making them an excellent option for anyone dealing with sensitive respiratory conditions. However, like FPR, MPR doesn’t give you a complete picture of a filter’s performance, especially in terms of air quality overall.

How to Choose the Right Filter Rating for Your Home

When choosing a filter for your HVAC system, consider your specific needs. If you're mainly looking to improve air quality by removing common allergens such as dust, pollen, and pet dander, a filter with a MERV 8 rating should be sufficient. If you're concerned about more minute particles like bacteria or viruses, you may want to opt for a higher MERV rating—somewhere between 10 and 13.

The MERV rating might not be enough for those dealing with odor issues, such as cooking smells, pet odors, or bathroom smells. Standard filters, even those rated at MERV 13, won’t effectively capture gases and odors. And that’s where Colorfil (NASA award-winning color-shift technology) comes in.

Why Colorfil is the Best Choice for Your Home

Colorfil filters are rated at MERV 8, which means they efficiently capture particles like pollen, dust, and pet dander. Now, what really sets Colorfil apart? It’s the patented gas-phase filtration technology. While traditional filters can trap airborne particles, they do very little to address odors or chemical vapors. Colorfil’s unique technology captures and binds gas-phase chemicals and odors at a molecular level, making them rich and highly effective at neutralizing unpleasant smells.

Whether it’s the lingering scent of last night’s dinner or the odor from your furry animal, be it cats, dogs, or any other pets, Colorfil goes beyond traditional filtration to purify your home’s air. And it doesn’t just stop at dust; it tackles the hard-to-capture odors that other filters can’t even touch. 

Plus, Colorfil's color-shift technology provides a visual cue to let you know when it's time to replace your filter. As it works, the filter changes color—from pink to yellow—indicating the removal of harmful chemicals and odors—a simple way to ensure your home always smells fresh and clean.