A couple of posts back, we explained the MERV rating used for air filters. Knowing your filters is an important part of choosing the right one and keeping you breathing easy. In this post, we’ll continue that discussion with a focus on some other rating systems, as well as how to decide which type of air filters are right for you.


MERV is most common, but here is a look at all of the rating systems and how to compare them:

  • Minimum Efficiency Reporting Value (MERV): MERV is the standard rating system used worldwide. Filters are measured on a scale of 1-16, with 1 filtering the least, and 16 filtering the most.
  • Microparticulate Performance Rating (MPR): MPR measures filter quality based on the smallest particles that can get through. The rank is a sliding scale from 100 to 2800. 
  • Filter Performance Rating (FPR):  FPR was created by Home Depot with a scale of 4-10, and is similar to MERV.

Here’s a quick key for comparing filter quality between rating systems:

  • MERV 8 = MPR 60 = FPR 5
  • MPR 1000-1200 = MERV 11 = FPR 7
  • MERV 13 = MPR 1500-1900 = FPR 10


Changing your filters is critical. A minimum of once every three months is vital to keeping you and your HVAC system healthy. Aside from keeping your air clean, it will reduce allergy triggers, reduce mold growth, and result in a lower energy bill! To see if you need a change, just check the filter to see if it’s dirty. If there’s a lot of dust and grime, that means the filter can’t work effectively and should be changed.


It may seem like you would want a filter with the highest possible rating, but that’s not necessarily the case. A high MERV rating is great if you have severe allergies, but it can limit the effectiveness of your HVAC unit as a whole by making it work harder. This can make your energy bills increase and could possibly reduce the life of the unit.


Sound confusing? It can be. Thankfully, the experts at The Bosworth Company can help you decide what filters are right for you! Schedule an appointment online or call us today at 432-570-5233. It’s Worth the Call. Always.