Look for HEPA or multi-stage filtration combined with a sealed or whole-machine system so trapped particles can’t leak back into the air. Washable or reusable filters are convenient, and pickup features (brushrolls and tools designed for pet hair and fine dust) help keep allergens contained inside the machine.
Useful non-filter features include sealed/anti-allergen systems to prevent leaks, one-touch or hygienic emptying to limit contact with dust, washable/reusable filters, self-cleaning brushrolls to avoid hair wrap, and odor-neutralizing technology.
Cordless models in the results most often list about 40 minutes of runtime; one model lists up to 60 minutes. Corded models provide continuous run time.
Some models use washable or reusable filters; at least one description advises cleaning or replacing the HEPA filter once a month to prevent clogging. Follow the manufacturer’s instructions, check washable filters regularly, and replace disposable HEPA elements as recommended.