A standard 1″ throw-away furnace filter is between 5-10% particle efficient. This means these filters will only trap about 5-10% of what passes through them. You can improve the efficiency of the filtration of your heating and/or cooling system by upgrading to either a media or electronic style filter. A media style filter’s particle removal efficiency is 60-65%, while an electronic style filter is 90-95%. By upgrading to either of these styles, you will also cut down on maintenance costs on the system since dirty systems are the #1 cause for malfunction.