What is a HEPA Filter?
“HEPA” stands for “high-efficiency particulate air” (filter). It sounds complicated, but HEPA air filters are nothing fancy. They were invented back in the 1940s when scientists were developing the atomic bomb, and they’re just a mat of randomly aligned fibers, made from either glass or synthetic materials. The synthetic material used in the air filter is similar to what’s used in quick-dry T-shirts.
On the other hand, fiberglass air filters are made from glass – that means things like silica, alumina, calcium oxide, boron oxide, magnesium oxide, sodium oxide.
What’s important about HEPA air filters is they’re incredibly effective at capturing almost every size of particle. They can capture viruses, bacteria, pollen, PM2.5, allergens, and more. HEPA air filters are the most important component of any air purifier.
What are the benefits of a HEPA filter
When you invest in a HEPA filter you are buying technology that has been tested and approved against a standard. This ensures the quality and reliability of the filter to remove even the tiniest airborne particles. Air filtration is actually more important than many of us realise as indoor air contains many different irritants and pollutants. A correctly chosen HEPA filter can ensure these pollutants are removed efficiently, vastly improving the quality of air you breathe.
Why is it necessary to remove such small particles from the air?
Microscopic airborne particles are nearly impossible to see, but can be taken into the lungs and be irritating or damaging to your health, especially for anyone who suffers from allergies or asthma. Larger particles such as pollen, mould spores, dust and other allergens are usually filtered out of our systems in the nose or throat – causing all of those unpleasant symptoms that allergy suffers face. These larger particles are easily removed from the air by a HEPA filter.
Smaller particles, such as PM 10 particles, which are only 10 microns in diameter make it past our throat and into our lungs. Even smaller particles, like PM2.5 particles which are 2.5 microns in diameter, can make it right down into the alveoli in our lungs, posing a serious health risk. Most of these tiny particles are pollutants resulting from fossil fuels, traffic or chemicals. It was estimated that small particulate pollution cause around 370,000 premature deaths in Europe in 2005. Scary stuff really! We’ve written a whole other blog post on this subject here.
It turns out that a particle that is 0.3 microns wide is actually the hardest to filter out of air. So if a HEPA filter removes 99.97% of particles that are 0.3 microns in size, it is even more effective at removing PM10, PM2.5 and the larger allergens such as pollen.
Popular reasons for choosing a HEPA filter
New parents – A HEPA air filter will remove pollutants from the air making it safer for young children (and adults) to breathe.
Smokers – You need an air purifier with both a HEPA filter and a carbon filter inside. The first to remove smoke particles and the second to remove the fumes, gases and associated odour.
Pet owners – A purifier with a life time HEPA filter will remove allergy causing pet dander from the air. Look for a purifier with both a HEPA and carbon filter to remove allergens and odour.
Asthma Sufferers – A well chosen HEPA air purifier will removing common household allergens like mould spores, dust mite feces and household dust particles., allergy sufferers can enjoy refuge from the unpleasant symptoms.
Where are HEPA filters used?
HEPA filters were originally intended to be used in lab and factory settings. Today, they’ve also made their way into consumer products, including cars, vacuum cleaners, and—you have known—air purifiers.