Fresh air does more than just purify the lungs – it enhances mood, improves digestion, and boosts energy levels. Unfortunately, as of 2023, about 36% of people nationwide live in areas with unhealthy ozone or particle pollution levels. Since residing in cities is inevitable, installing air purifiers is the next best option to avoid contact with harmful indoor pollutants like argon and radon. However, one should avoid certain common mistakes when buying an air purifier: Forgetting to check the air change rate Air change rate or air changes per hour (ACH) indicates how often an air purifier filters all the air in a room within one hour. However, this number may differ among rooms, so one should evaluate an air purifier’s ACH based on the recommended number for different types of rooms. For example, a room with several plants might require a minimum ACH of 4, which can help eliminate pollen, dander, etc. In contrast, an ACH of at least 6 is essential for larger rooms with no plants or pets. One should check the ACH readings of the cleaner in different rooms, compare them against the recommended ACH, and shortlist the one whose ACH comes closest to the recommended values.