Air purifiers are ideal household appliances to improve indoor air quality by eliminating dust, pollen, bacteria, harmful gases, and other allergens. You might need an air purifier if you observe the following signs: Allergy symptoms such as stuffy nose, itchy eyes, sneezing or coughing - Bad odors in your home - The air feels stuffy and stale - Asthma flare-ups - Dust on your furniture - If you snore loudly