Our recommendation for people with allergiesPeople with house dust allergies should look for a vacuum cleaner with a HEPA filter fitted as standard and specially sealed casing. These appliances ensure that the filtered air discharged from the vacuum cleaner is cleaner than ambient room air before vacuuming. Based on these characteristics, some Miele vacuum cleaners are specifically recommended for people with allergies by TÜV Nord, a German material testing institute. In order for the appliance to maintain high filtration performance throughout its service life, the saturated, clogged HEPA filters must be replaced regularly – about once per year.