Air Purifiers For Dust
Dust, mold spores, volatile organic compounds, pet hair and dander and cigarette smoke can all contribute to your allergies. Air purifiers can reduce these pollutants and prevent them from irritating your lungs and nose.
But the type of air purifier you buy will depend on your allergy triggers, according to McKeon. To help you find the best one for you, consider these factors:
HEPA Filtration
The best air purifiers use HEPA filters to remove dust and other allergens from indoor air. A HEPA filter consists of a mesh of randomly placed layers of cellulose, synthetic fiber or glass fibers. Air flowing through the filter passes erratically, and particles are more likely to hit and stick to these fibers than to pass through them. This causes the particles to be ensnared in the fibers and removed from the airflow.
A HEPA filter can trap up to 99.7% of airborne particles as small as 0.3 microns. That includes not only fine dust and dirt, but also mold spores and other organic debris from the outdoors. It can even capture some microscopic viruses and bacteria, including Aspergillus niger, Penicillium citrinum and Staphylococcus epidermidis.
However, relying solely on an air purifier for dust removal isn’t recommended. The EPA recommends combining other techniques, such as dry steaming furniture and carpets, vacuuming carpets and switching out bedding for an allergen-proof alternative, to minimize the amount of dust in the home.
When shopping for an air purifier, make sure that it has a high clean air delivery rate (CADR) and that it is the right size for your space. This independently verified rating shows how much cleaner air your device produces per minute and in air purifiers for dust square feet, and it can be used to compare one model against another.
Carbon Filtration
Carbon filters are the workhorses of air purifiers, absorbing and trapping a broad spectrum of volatile organic compounds. They are especially effective at removing odors, chemicals and gases from the air. This is accomplished through a process called adsorption, which happens when a pollutant sticks to the surface of the carbon, much like it would stick to a sponge.
Activated carbon is a porous substance that contains a huge number of microscopic holes and cracks. It’s commonly found in granular or powdered block form, with one gram of carbon having a surface area equivalent to 500m2. The material has been treated with heat or steam to make it even more porous and increase its ability to hold contaminants.
These filters are designed to remove gases and vapors from the air, which is why they’re commonly used in conjunction with other types of filters. They’re typically able to remove VOCs, which are air purifiers for dust the volatile organic compounds that cause things like secondhand smoke and fumes from paints or cleaning products to be released into the air.
They can also help reduce odors in the short term, making them good for homes that have recently been affected by wildfire or home renovations. They can’t, however, address particulate pollutants. Replacing a carbon filter can be expensive, and it’s difficult to know when it’s saturated, so they’re best used in combination with other filters.
Multistage Filtration
A multistage filtration system enables multiple stages of filtering to occur in parallel and at different times. This method allows the highest level of efficiency in the smallest volume of space, while reducing maintenance costs and power consumption.
The first stage of this system uses a filter with large particles to collect dust. The next layer is a HEPA filter with smaller particles. Finally, the last layer is a carbon filter that absorbs harmful gases from the air. These systems are especially effective for those with sensitive allergies or respiratory problems.
NASA’s Glenn Research Center has developed a technology to keep high-efficiency filters from becoming overloaded with larger particles. The innovation employs a system of inertial separation and impaction methods on collection surfaces, which are automatically cleaned by an innovative feed system when they become heavily loaded. This approach significantly reduces maintenance costs and extends the life of high-efficiency filtering devices.
The patented MultiStage Filtration (MSF) technology has been shown to be a robust, sustainable technology that is compatible with local conditions and available management capacity in communities. It is a combination of coarse gravel pre-filtration and Slow Sand Filtration, and can treat water with contamination levels above those that can be treated by SSF alone. It has been demonstrated in a number of pilot projects and is being applied in many countries.
Noise Level
If you want an air purifier for dust that will let you sleep soundly, look for one with a low noise level. Many models produce a quiet hum that goes unnoticed, even at their highest fan speed. When shopping for a silent purifier, keep in mind that most manufacturers list their decibel ratings at the lowest fan speed or in a ‘Sleep’ mode, so you’ll want to open up the specification sheet and check out their maximum dB rating (at full-out).
If your home is heavily smoke-filled, or you live in an area impacted by wildfires, it’s also important to find a quiet air purifier with the ability to remove smoke particles from your indoor air. For this, you’ll want a model with an excellent CADR rating and a low noise level. The Blueair Protect 7470i, for example, has a record-setting low decibel rating at the lowest fan speed and operates quietly enough to use while you’re sleeping.
Other features to consider include odor control, temperature control and smart device connectivity. Some top-rated models have the ability to connect to Wi-Fi, can be controlled by voice assistants like Amazon Alexa and Google Assistant, and automatically adjust their settings based on your indoor air quality over time. They may also have a digital display that can change colors to indicate when it’s time to replace the filter.
