Yes, an air cleaner with a HEPA air filter will remove dog hair. Larger particles such as hair will often be trapped by the pre-filter before it even reaches the HEPA filter. Therefore, having a convenient quick-change pre-filter is important for pet owners so that the filter can be vacuumed or changed as required (usually every three-months at minimum with dog hair). All AllerAir numerical series units (4000, 5000, 6000) have a quick-change pre-filter ---you simply reach under the unit and pull it out, no tools required!
It's important to note that air cleaners are designed to remove particles that are airborne. If you run your air cleaner 24/7 you will notice a difference in the level of dog hair and dander in your home, however it's wise to include a HEPA vacuum in your cleaning routine to remove hair that lands on carpets and furniture.
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