Poulton Le Fylde, FY6 8JU, UK

What is the difference between absolute and nominal ratings?

What is the difference between absolute and nominal ratings?

• Nominal rating usually means the filter can capture a given percentage of particles of a stated size (e.g. 50% @ 10 micron). Absolute rating is the smallest typical particle size retained by a filter media at 98+% efficiency. This is also referred to as the Beta=75 or 98.67% efficiency rating.