You probably have come across the terms 'HEPAfilters air purifiers' or "HEPAfilter air purifier' when searching for air purifiers online, but what do these terms mean? In this article, we explain all you need to know about Air Purifiers that claim to be HEPA, “HEPA like” or are labelled as “True HEPA”.

 

Do not fall for the hype. While most air purifier suppliers advertise their products as being “True HEPA” or “HEPA-like," this could be far from the truth. HEPA, or High-Efficiency Particulate Air, is an air filtration technology with a removal efficiency,of 99.95%, and not all air purifiers on the market today can do that.

 

Here is how it works:.

HEPA air purifier, how do they work?

To understand what a HEPA filter air purifier does, we need to consider the size of airborne particles, especially those that affect the air quality in our homes. These are referred to as particulate matter, and they can be anything from pet hairs on your sofa to pollen pores floating in from outside.

 

 

Particulate matter is measured in microns, or μm, a unit that measures the diameter of a particle to reveal its size. Large particles like beach sand are said to be 90 microns (μm) in diameter, while human hair is about 70 μm in size. Dust and pollen are 10 μm, while smaller particles like smoke gums are measured at 2.5 μm.

 

A HEPA filter can remove airborne particles that are smaller than 2.5 μm up to 0.3 microns or μm. This includes particles like mould, smoke, dust, pollen, pet dander, human hair, and so on. With such a high removal efficiency, a HEPA air purifier is widely used in areas where constant air purification is needed, like hospitals, hospices, clinics, dental offices, ICU units, and so on.

 

Common Air Pollutants in Microns

Particle	Microns  (μm)
Tobacco Smoke	0.01 - 4
Typical Atmospheric Dust	0.001 to 30
Lead Dust	0.1 - 0.7
Burning Wood	0.2–3
Liquid Droplets	0.5–5
Pet Dander	0.5 - 100
Asbestos	0.7–90
Coal Dust	1 -100
Mould Spores	10–30
Pollen	10 - 1000
Human Hair	40 - 300
Beach Sand	90 - 10000

 

Note that particle pollutants are usually categorisedinto two;

● PM10 particles: particles that are 10 μm or lower and can be inhaled

● PM2.5 particles: these are fine particles that are 2.5 microns in diameter or lower.

 

The PM2.5 particles are the most dangerous. When inhaled, they are easily absorbed into the bloodstream and can infiltrate the heart, lungs, and brain.

 

Should an air purifier have a HEPA filter?

Absolutely. With the air around us becoming increasingly polluted, now more than ever, we need to consider an air purifier with HEPA filter technology to remove as many pollutants as possible from our homes. Especially if you have a toddler, caring for a senior, or live with someone with respiratory allergies.

 

So, which air purifier with HEPA filter to buy in uk?

It is important to note that some air purifiers that are classified as HEPA are not HEPA air purifiers. They usually have terms like “HEPA-like” or “True HEPA”, which is usually a marketing gimmick to get the customer to buy their products. Most “True HEPA” or “HEPA-style” air purifiers are merely EPA air purifiers.

 

The secret to knowing if an air purifier is HEPA-certified is by looking at two things:

● Efficiency

● Most Penetrating Particle Size or MPPS

 

Efficiency refers to how capable an air purifier is in removing air impurities. This efficiency is usually given as a percentage, and the higher the percentage, the more efficient the air purifier will be.

 

Most Penetrating Particle Size, or MPPS, refers to the ability of a particle to easily pass through the air purifier's filtration system given its size. MPPS is given as a percentage, and the lower the percentage, the more effective the air purifier will be in filtering out the tiniest of particles.

Are EPA filters “True HEPA”?

EPA filter stands for “Efficiency Particulate Air” filter. This type of filter has an efficiency of 85% to 99.5% and can capture dust particles and other airborne allergens that can cause infections. However, there are tiny micron particles that an EPA filter cannot remove efficiently, so you are not getting the full protection against the airborne allergens you need.

 

“True HEPA”, “HEPA -like”, or “HEPA-type” is only a marketing term for the EPA air purifiers, but they do not meet the air purification standards of the HEPA air purifiers used in medical settings.

 

 

The Best HEPA air purifier

When looking for HEPA filters air purifiers, the marketing term you should be keen on is “Medical-grade HEPA” filter. These are HEPA filter air purifiers that have been tested and proven true to their claims by filtration efficiency standards such as EN 779 and EN 1822. Classification is also based on a rating known as the Minimum Efficiency Reporting Value.

 

The Minimum Efficiency Reporting Value

The minimum efficiency reporting value, or MERV, refers to an air filter’s ability to trap air particles that are between 0.3 and 10 μm. The MERV rating is recorded on a scale of 1–16, and the larger the number, the more efficient the HEPA air purifier is.

 

Here is a table to illustrate.

 

Minimum Efficiency Reporting Value (MERV)	Particle Size in μm
E1 to E4	3.0–10
E6	3.0 to 10 (49.9% more efficient)
E8	3.0 to 10 (85% more efficient)
E10 to E11	1.0 to 3.0 (50% more efficient)
12	1.0 to 3.0 (80% to 89.9% more efficient)
H13 to H14	0.3 - 1.0
H16*	0.3 to 1.0 (75% more efficient)

 

* HEPA H16 air filters are designed for commercial and industrial use and are not suitable for domestic use. They are more expensive, larger, and have a higher air flow rate than standard HEPA filters, making them more suitable for large spaces such as offices, hospitals, and factories. In addition, they may require more maintenance than standard HEPA filters.

H13 Air Filter vs H14 Air Filter, which is better?

According to the EN 1822 classification system, the best HEPA filters air purifiers units are those classified as H13 and H14. The H13 and H14 filters are commonly marketed as “Medical-grade HEPA” air purifiers.

 

A H13 HEPA air purifier works with 99.99% more efficiency compared to a “True HEPA” air purifier. While a “HEPA-type” air purifier gets rid of pollen, dust, mould, bacteria, dust mites, smoke, lead, and pet dander, an H13 HEPA filter goes beyond that.

 

The H13 air purifier will get rid of tinier particles up to 0.3 microns. This includes airborne allergens such as;

● Asbestos

● Paint pigment

● Insecticide

● Anthrax

● Carbon dust

● All bacteria

● Tobacco smoke

● Virus carriers

 

It gets better.

 

 

Although H13 and H14 air purifiers are rated as PM0.3, meaning they can filter up to 0.3 microns, these air purifiers, to some extent, can filter allergens smaller than 0.3 microns. This is made possible by a phenomenon known as Brownian motion.

 

In Brownian motion, particles move in an irregular motion instead of assuming a regular movement. Particles below 0.3 microns do not move in a straight line but tend to zigzag about. It is this irregular motion that makes it possible for a 0.3-micron HEPA filter to capture them. The tiny particles bounce around and get caught in the fibres that make up the filter.

 

This is how a HEPA 13 air purifier achieves its 99.995% removal efficiency compared to an EPA filter that only manages 95% efficiency. And given its penetration efficiency of 0.05%, a H13 will be effective in reducing viruses, bacteria, paint pigment, asbestos particles, insecticide particles, and practically any other tiny molecular particle in your home that ruins indoor air quality or triggers allergies.

 

Another feature to consider is the clean air delivery rate in HEPA 13 and 14 air purifiers.

What is the Clean Air Delivery Rate?

Clean Air Delivery Rate, or CADR, is a rating that indicates the volume of clean and filtered air an air purifier can produce with regards to room size. This rating is measured in cubic feet per minute, or CFM. Ideally, the CADR rating on a HEPA air purifier will dictate the room size it can be used in. For example, a compact H13 air purifier with a CADR of 42 CFM will be effective for small spaces, while an air purifier with a CADR rating of 200 CFM can be used in larger rooms.

Do HEPA air purifiers filter out the COVID-19 virus?

A HEPA air purifier can reduce the spread of the COVID-19 virus when used correctly. In the “Effectiveness of HEPA Filters at Removing Infectious SARS-CoV-2 from the Air” scientific study, scientists discovered that a HEPA filter air purifier can filter out the Covid virus, SARS-CoV-2, with a removal efficiency of 85.38%, 96.03%, and 99.97% continuously.

 

The United States Environmental Protection Agency further suggests using a combination of an H13 air purifier and a suitable air conditioner to effectively reduce the spread of the COVID-19 virus indoors.

 

 

When to change HEPA filter air purifier?

Replacing the HEPA filter in your air purifier is important to ensure the unit continues to operate at 99.95% removal efficiency. The best time to change the HEPA filter is when;

● It has a clump of dirt

● It discolours due to dirt

● The air purifier takes more time to purify air than before

● It is damaged

 

Ensure the air purifier replacement filter you choose matches the model of your air purifier. Most HEPA 13 replacement filters should last 6 to 12 months before the next replacement.

 

Conclusion

We hope this article clarifies the difference between a “True HEPA”,  “HEPA-like”, and a “Medical Grade HEPA” filter. Always go for air purifiers with a “Medical Grade HEPA” 13 or 14 air filter, as they are proven to be more efficient compared to the EPA filters. Also, the easiest way to tell if an air purifier will be effective in the room in which it will be used is by checking the CADR rating of the product.

 

FAQs

Can air purifier help snoring?

Yes, air purifiers can help reduce snoring. One of the causes of snoring is allergies, which can be brought about by allergy-causing particles in the air. When pollutants in the air are inhaled, they irritate the membrane lining the nose and throat, causing it to get inflamed.

Can air purifiers help asthma?

Air purifiers are effective in reducing the allergens that trigger asthmatic reactions. Common asthma triggers include allergens like pollen, smoke, or airborne chemicals. You must get an H13 HEPA air purifier, which can remove airborne allergens like pollen and even allergens that are below 0.3 microns in size, like paint pigments and carbon dust.

Which HEPA filter?

The right HEPA filter should be able to filter out airborne allergens with 99.99% removal efficiency. Although EPA air purifiers are labelled as “True HEPA” or “HEPA-like”, they are not as effective as a "Medical Grade" H13 or H14 air purifier. An H13 HEPA filter has a 99.995% removal efficiency with a 0.05% penetration; this is the best air purifier for homes, hospitals, clinics, and any environment that requires high pollutant removal efficiency.

Can HEPA Filters stop Covid?

The right air purifier can help reduce airborne contaminants such as viruses that can cause diseases like Covid. Get an H13 HEPA filter to remove bacteria, mould, and exhaled droplets carrying the COVID-19 virus. A combination of a portable air conditioner and a HEPA-13 air purifier will effectively reduce the spread of the COVID-19 virus.