Miele's HEPA AirClean filters meet Europe's stringent HEPA 13 standards, capturing over 99.95% of all particles, down to 0.1 microns. Once activated, a TimeStrip® releases a red line of liquid over the course of one year, reminding users when it's time to replace their filter.

The completely sealed systems in Miele C2 , C3 and S4000, S5000, S6000, and S8000 series canisters, when equipped with Active Certified HEPA Filters, will retain 99.95% of pollens, household dust, dust mite droppings and other allergens as small as 0.1 micron in size. This filter is highly recommended for those who have dust related allergies or asthma.This filter fits in the same place as the Active Air Clean or Super Air Clean Filter. You can not use more than one exhaust filter at the same time. SF-HA 50