Miele stays airtightFor people with house dust allergies, we recommend a vacuum cleaner with a HEPA filter fitted as standard. TÜV Nord (environmental testing board in Germany) has also recommended several Miele cylinder vacuum cleaners with HEPA AirClean filters for people with allergies. With the special casing seal the whole appliance, not just the exhaust filter, meets the requirements of TÜV Nord, which are reviewed annually. The filtered and discharged air is cleaner than normal room air. In addition, bacteria, allergens and mould spores remain safely in the dustbag.