Using HEPA filters can trap contaminants and help relieve allergies. HEPA stands for High-Efficiency Particulate Air and is a type of mechanical air filter. It works by forcing air through a fine mesh that traps harmful particles such as pollen, pet dander, dust mites, and tobacco smoke. If you're plagued by allergies and have done all you can to reduce allergens in your home, an air filter could be the answer.
Air purifiers can help with respiratory health, not just allergies. Make sure to buy one that uses a proper HEPA filter and avoid any products that produce ozone. However, an air purifier is not a panacea and there is very little medical evidence to support that it directly helps improve health or relieve allergies and respiratory symptoms. This is partly due to the fact that it is difficult to separate the effects of known air quality pollutants in your home from other environmental and genetic factors.
If you suffer from an allergy or asthma, an air purifier with a HEPA filter may be useful for you as it will be good at removing fine particles in the air. If your home has ducted heating or air conditioning, it is possible to add filters to your air handling system. The disadvantages of air purifiers include noise, energy consumption, and the cost of replacing filters. Research has shown that for cat and dust mite allergens, which are predominantly found in particles with a diameter of several microns, the expected reductions in interior mass concentrations ranged from less than 20% for the typical and inexpensive oven filter (fabric fiberglass) without ASHRAE rating at 60% for a HEPA filter.
An air purifier removes particles, gases, and other contaminants from indoor air, making the air cleaner to breathe. The appliance industry has established a Clean Air Supply Rate (CADR) to allow consumers to adapt the right room air purifier to the room they want to treat. The researchers concluded that while the use of a portable air purifier “will provide exposure benefits in the room you are in”, it is not likely that concentrations of common asthma triggers throughout the residence and the corresponding personal exposures will be mitigated. They also concluded that high-efficiency duct air cleaning systems would produce a more substantial reduction in personal exposure than portable air purifiers used in intervention studies published to date. HEPA filters can clean smaller particles such as tobacco smoke and medium and large particles such as dust and pollen from the air and can have a high CADR. Activated carbon filters will be better at removing odors but not as good at removing pollen from the air.
To get the best results, make sure that the air purifier you have is in the room you spend the most time in, that it has a suitable HEPA filter installed, and that it is running all day. You can also order custom filters that target specific allergens and impurities such as pet allergies, filters that absorb toxins, germs or odor removers. Residential air filtration can be provided by filtering the entire home through the home's heating, ventilation or air conditioning system, using portable room air filters or a combination of both. Other problems such as air bypass due to poor filter fit and duct leaks can further confuse filtration efficiency in HVAC systems. As air moves through the filter, contaminants and particles are captured and clean air is expelled into the living space.