A simple question, but can be a complicated answer.
- Try not to place next to a wall if possible. You want air flow.
- If you know who’s infected, next to them (typically placement in a patient’s hospital room).
- If you are in a classroom, you will want 2. Place one in the center of the room, even if you have windows open. Place the other in the middle of the room, but up near the teacher.
“I just bought a portable HEPA air cleaner. Where should I put it in the classroom? To be effective, portable air cleaners need to get as much of the air in the room through the filter as quickly as possible. Think about trying to beat an egg in a square pan. If you try to beat the egg with your mixing device in the corner or on an edge, the egg in the far side of the pan will not get stirred very quickly. However, if you place the beating device in the middle of the pan, the egg will mix faster (but still not perfect in the corners).
Likewise, in a classroom, you want to place an air cleaner as close to the middle of the room as possible, elevated up off the ground. This will maximize the amount of air moving through the HEPA filter. Make sure you place the air cleaner in a location where it won’t fall onto someone and secure the cord to prevent any tripping hazards.
Most portable air cleaners draw air in from the sides and exit on the top. Many Do-It-Yourself filters made with box fans and filter furnaces exhaust air to the side. These DIY designs should not be placed on the floor as the exiting air may resuspend particles from the floor that may contain viruses.
Operate your portable HEPA cleaner on its highest setting. The higher the setting, the more air that moves through the filter and lower the virus concentrations will be in the air. Hence, highest setting equals lowest risk for people in the classroom. Lower settings maybe desirable due to fan noise, but be aware they will increase risk as less air is moving through the filter.”