I do believe Air Purifier is machine that must be in each house. Thank you for providing list of Air Purifiers. May I ask how good are the filters in these air purifiers and how often will they need to be changed? I read on the internet that sleeping with the air purifier is very beneficial. Sleep becomes healthier and more pleasant. That is why I had a desire to buy myself the same device for my home so that it would be more pleasant to exist in it. I've already found a service where there is a fairly large catalog of various air purifiers https://dehumidifiercritic.com/best-large-room-air-purifier/ . Not only do they just have a review for each product, but all the pros and cons of each product are also written there. In addition, I read that each purifier is tested for about 3 months before being reviewed. It sounds pretty cool doesn't it? Still I really want to know the answer to my question please.

All interior spaces need daily fresh air. even in times of extreme weather (hot or cold or humid). The not free but most comprehensive way to do it in a house is to have an ERV or HRV fresh air device installed by an HVAC contractor. They bring in outside air and temper the incoming air using outgoing air (using a heat exchanger to extract the heat or coolness, depending on the season) to avoid the extreme temperature differences. The fresh air is realesed either directly into a room through a vent or into an existing HVAC system duct. A no-cost way to bring in regular outside air is to turn on a bathroom exhaust fan, leave the bathroom door open and then open a window an inch or two in a different part of the house. You should feel an incoming airflow through the open window and that works even if there's no breeze at all outside. The old fashioned way still works too - open two (not one) windows on opposite sides of the home.

Depends on if you plan to pay to have maintenance performed regularly on it. (You never stop paying for it... filters, bulbs, etc.) The cheaper models may do more harm than good or virtually nothing at all. (produce ozone) The better models that do the best cost $$$. Typically these are only worth it if you have someone who suffers from allergies... and you maintain it which can easily cost $250 or so a year for the better models. If you don't do the maintenance it will lose effectiveness over a years time. So you may as well keep the money in your pocket if your plan doesn't include maintaining it. Strap on a few more masks... if you can't breathe imagine how your poor HVAC system feels. Listen to the science. LOL. I don't recommend trying to DIY this either. I service the Katy, Texas area. (prepaid maintenance contracts so easy an autistic child of two could do it.)

Zero maintenance? Yeah you just replace the contraption every 3 years or so after the product warranty runs out. Nothing on this planet has zero maintenance. (gimmick) If you don't test it to make sure it's working? *see maintenance. Then it just sits there doing nothing. (zero maintenance as it were.)