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What is MERV? What about MFR and FPR?Updated 3 months ago

Short Answer: 

MERV, MFR, and FPR, are reporting standards for filter efficiencies (or performance levels). Basically, the higher the rating, the more the device filters out. Just keep in mind that the more you try to filter, the harder it is for air to pass through the filter (and therefore the more energy your HVAC will use to suck the air through the system). 

Rating systems compared

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Long Answer: 

Merv is actually not a person! Okay, just kidding :) MERV stands for Minimum Efficiency Reporting Value and measures how many particles the filter can block out. MFR (Microparticle Performance Rating) and FPR (Filter Performance Rating) are other rating metrics that serve the same purpose. 

Below is a chart comparing these rating systems:Overall, the key takeaway is that the higher the number (MERV/FPR/MFR), the tighter the fibers, and, therefore, the more the device can filter out. Just keep in mind that the more you try to filter, the harder it is for air to pass through the filter as well.

Fibers tighten as MERV rating increases

With so many standards and acronyms, knowing the best filter for you can get a bit complicated. If you need help filtering out this confusion and finding what's best for you, take our quiz or reach out, we're here to help!

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