| It's time to reveal the truth about home air | | | | number of air changes per hour, possibly only one |
| purifier room size ratings. They're exaggerated. | | | | For typical allergy relief four air changes per hour |
| Consumers are deceived into buying home air | | | | is needed. Any respiratory problem more serious |
| purifiers that will never deliver the expected | | | | than allergies requires six air changes per hour. |
| performance. Here's how you can be a savvy | | | | Airflow rates should obviously be based on what |
| shopper. | | | | the home air purifier can deliver against the |
| You're Being Lied To | | | | resistance of installed filters. And you should be |
| If you need serious air purification at home to | | | | able to get the needed performance at a |
| reduce allergy, asthma or MCS symptoms then | | | | reasonable fan speed and noise level. |
| properly sizing your home air purifier is essential. | | | | Most people end up with less air purification than |
| So you check the side of the box and it says | | | | they need. It's far better to install excess |
| "Good for rooms up to 250 square feet." That's | | | | capacity to care for times when pollutants are |
| plenty big enough for your little bedroom you | | | | especially high. Lower and quieter operation |
| think. | | | | speeds can be used for maintenance for normal |
| There's just one problem. That home air purifier | | | | day to day needs. |
| size rating is a complete fabrication. Here's why. | | | | Where can you find reliable and accurate size |
| Room size ratings are based first and foremost | | | | recommendations? Two excellent resources I turn |
| on the manufacturers' desire to boost their own | | | | to are and These merchants evaluate actual air |
| image. Numbers are massaged as follows: | | | | being delivered by home air purifiers with filters in |
| - Ratings are based on maximum fan speed, | | | | place at every fan speed. They also base their |
| typically too noisy for most people | | | | recommendations on four to six air changes per |
| - Ratings are based on "free flow" by which they | | | | hour. This gives you a better idea of how well an |
| mean with no filters installed | | | | air cleaner will actually perform for you. |
| - Room size ratings are based on a reduced | | | | |