An air purifier that exchanges air two to eight times an hour can reduce indoor pollution by more than 80 percent. Of course, its efficacy depends on various factors, including placement and room size.
Unless you buy a purifier that connects to your existing HVAC system, you will need to choose a room for the unit. Most homeowners prefer the bedroom, kitchen or bathroom (or all three). The reasoning: you spend the most time in your bedroom while the kitchen and bathroom have the greatest amount of bacteria.
Regardless which room you choose, there are other placement strategies to consider.
Location of Contaminant
Ideally, the air purifier should reside closest to the source of the pollution. For example, besides the household smoker’s favourite chair. The nearer the source, the earlier it will trap the particles.
Interestingly, placing a purifier by the door can catch the particles before they enter the room. Such a placement benefits households with allergens most. For instance, if you’re semi-allergic to cats but own one anyway, you can place a purifier by your bedroom door to stop dander from floating into the sleeping area.
Airflow and Circulation
An air purifier sucks from the front. If placed near furniture or some other obstruction, it cannot draw in the pollution. That said, the centre of a room is not a good spot either.
Because of diffusion, the best spot for an air purifier is to the side of a room (whichever is most open). The principle of diffusion dictates that particles will spread across the room at an equal distance from one another. Thus, as the machine intakes air, the particles will naturally start to fill in the gaps. As it pushes clean air out, it will create airflow. If placed in the middle of a room, creating such circulation would be more difficult.
