How Many Air Purifiers Do I Need For My Home?

Clean air is essential to good health. Microscopic particulate matter, known as PM2.5 can cause lung damage, cognitive impairment, and a shorter life span. In fact, 4.2 million people a year die from exposure to PM2.5. The best way to make sure your indoor air is free of these deadly pollutants is to use a high-quality air purifier with a True HEPA filter. But, how many air purifiers do you need to keep your family safe? There are a number of factors to help you decide.

What’s the floorplan of your home?

Air purifiers with HEPA filters rely on air flow to work properly. This means that, while there will be some residual cleaning effects of those areas immediately surrounding the main cleaning area (such as hallways or foyers), the direct location where the air purifier is placed will be the one that has the most reliably clean air. 

An air purifier can not go through walls, around corners, down hallways, or even flights of stairs to clean the air in a living or working space. That means that homes with multiple rooms will generally require multiple air purifiers. This also means that indoor spaces with open floor plans may potentially require fewer purifiers.

How big are your rooms?

Room size is essential in determining how many purifiers you’ll need. To determine which purifier you’ll need for each room it’s important to take the CADR into consideration.

CADR stands for Clean Air Delivery Rate. CADR indicates how much air is filtered in an hour for three particular pollutants (smoke, pollen, and dust) in Cubic Feet Per Minute (CFM). The higher the CADR number, the faster the air purifier filters the air.

Buying an air purifier that is too big for your room is an unnecessary waste of money and energy and using one that is too small will affect your air quality. Doing some simple math can help you find just the right size unit for your room.

Follow the ⅔ Rule 

Generally, the CADR of your air purifier should be equal to at least two-thirds of the room’s area.

So, for example, a room that is 15 feet by 10 feet has an area of 150 square feet. ⅔ of 150 is 100, so an air cleaner for that room should have a smoke CADR of at least 100.

There are also online calculators available to help determine the minimum CADR you’d need for each particular room.

An exceptionally large room will require either one very powerful purifier, or a few well-placed smaller ones.

Where will you be placing your purifiers?

Air purifier effectiveness is largely dependent on where the purifier is placed.   While air purifiers are fantastic at pulling in air, they work best when they have access to a lot of air and good airflow. The more air that’s available to the purifiers, the faster they can clean it.  Placing your purifier near windows or doorways will allow for the most air to enter your purifier and be cleaned.

Another reason to place air purifiers near entry points is that moving air has enough energy to lift dust, mold, and many other particles and distribute them around your house. Using a purifier near entry points makes your indoor air cleaner because you are able to eliminate the pollutants before they lower the air quality of the rest of your home. 

It’s generally a good rule to make sure that the air purifier has at least a foot of space on the front, back, and sides of it so it will clean the air in the entire room. This means avoiding placing the purifier in corners and keeping the room as obstacle-free as possible.  

Vertical airflow is also something to consider. Placing an air purifier 3-5 feet off the ground allows you to be able to capture both the horizontal and vertical air movement which will increase the ability of your purifier to clean the air. Smaller units can be placed on a table or desk while larger units can sometimes be mounted on the wall.

Which rooms are the highest priority?

Most of us spend around 90% of our time indoors. Since indoor air is typically 2 to 5 times more polluted than outdoor air, it’s essential to ensure high-quality indoor air. When deciding which rooms to use a purifier in, there are two major factors to consider:

Level of pollutants

Pollutants can enter your home both through human activity and outdoor air seeping in. Activities like cooking, heating, cleaning, painting, and using scented products can all contribute to pollution. Rooms which are used by pets are also likely to contain more pollution due to pet dander. Kitchens, basements, and bedrooms are all areas that generally contain the highest levels of pollution.

How much time you spend in each room

While kitchens and living rooms may seem like where we usually hang out at home, the truth is that most of us actually spend the most hours in our bedrooms. That’s because sleeping takes us a whole third of our lifetime.

It’s particularly important to keep the air clean in your bedroom because of how important the quality of our sleep is to our overall health. Sleeplessness can affect your work, your education, and your risk of injury. People with sleep disorders are more vulnerable to a myriad of health problems including heart disease, high blood pressure, strokes, diabetes, and obesity.

While any pollutants can hamper your sleep, there are some that are more damaging than others. Allergens such as ragweed, dust, and pet dander can disrupt the periods of deep breathing that are essential to healthy sleep. 

Volatile Organic compounds (VOCs), which are released by many common everyday products, can also cause sleep problems. Breathing in VOCs while you’re sleeping affects the central nervous system and can lead to respiratory problems like sleep apnea. 

So, how many purifiers should you purchase?

The truth is that to really ensure the best quality air, every room in your home should have an air purifier. But, if that isn’t an option, determining which rooms to prioritize and where to place your purifier can make a major difference in how effective your purifiers are. If purchasing multiple purifiers is not an option for your family, moving purifiers from room to room as needed can be helpful.

Once you determine how many purifiers you need, check out the range of options we have at aeris to find just the right sized purifier for any room in your home. aeris purifiers remove both dangerous particulate matter and gases so you and your family can live longer, healthier lives.

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