DO AIR PURIFIERS REALLY WORK?
Do Air Purifiers Really Work?
Maybe you suffer from asthma or hayfever? Maybe you’ve received one too many pop-ups about the air quality in your area. Or maybe you’ve heard that an air purifier can help prevent the spread of Flu & viruses such as COVID-19. Whatever your reason, you’re possibly wondering whether getting an air purifier is a good idea, but deep down, you can’t help but ask the question: Do air purifiers really work?
The promise of what an air purifer can do sounds enticing An appliance designed to clean the air in your home, get rid of all the impurities including odours, dust, pet dander and help prevent you from getting airborne infections. But do they really deliver on that? Or are they just overpriced fans? Like anything relatively new, we want to know if it’s worth the investment, right?
For a start, why are people investing in air purification?
The US Environmental Protection Agency (EPA) has concluded that in room air filtration is one of the most effective ways to improve indoor air quality.
Firstly, for those who suffer with allergies to pet dander, smoke, and/or dust or have another respiratory condition – you know just how much they can cause your symptoms to get worse. There is no cure for allergies, but the presence of an air cleaner has been proven to dramatically reduce the negative health impact as the harmful particulate matter gets filtered out of the air before it reaches your lungs. Hence, many sufferers of asthma for example, have been utilising air purification for years to help them to breathe easier.
Secondly, many buildings and homes are under-ventilated meaning that there is a limited flow of air. In these circumstances, if a harmful airborne pathogen is present in the air it can rapidly cause a contamination outbreak. It’s been proven that one infected person in a shared and under-ventilated space can cause 5 others to become infected within 1 hour.
Furthermore, the Covid-19 pandemic has enlightened the global population that many viruses and harmful illnesses are spread through airborne transmission. It is also an established fact that indoor air quality is very often 3-5x worse than it is outdoors. Unless there is a means to filter the air, there is a risk of catching viruses and falling prey to fine particulate matter pollution which can cause or worsen respiratory conditions.
Ok, So how does an air purifier work?
There are a variety of air cleaning technologies on the marketplace but the most commonly found (and most effective) utilise HEPA filtration, preferably H13 or H14. The exact mechanism of how the air is cleaned will differ between different brands and types of air purifiers.
In it’s basic form, a purifier will suck the air into the device via an internal fan system. The air will pass through multi stages of filtration. An activated carbon filter will help capture the bacteria particles that cause odours, formaldehyde & VOCs. The HEPA filter will then trap the fine particulates like viruses, dust and other harmful airborne pollutants. The efficiency of different filter types will vary. For example a HEPA 14 filter is the the Zonitise recommended standard and will capture 99.997% of particulates as small as 0.3 microns. Finally, the filtrated, clean air will be recirculated to the room through the fan and this process is repeated every 10-15 minutes to ensure all the air within a space is purified at least 4x per hour.
Remember that not all air purifiers work in the same way. Some work by neutralization rather than drawing in and filtering the air. For instance, they may distribute negative ions that attract particles through static, and neutralize them. Alternatively, Ultraviolet Light (UV) is used to send to kill bacteria and mould. From decades of successful use though, we strongly recommend HEPA filtration as your first port of call.
Seriously, can an air purifier help prevent me from capturing Covid-19 and other illnesses?
In short – Yes if you use the correct level of filtration. A study by Curtuis et al found that in room air purification can reduce the likelihood of inhalation of respiratory pathogens by a factor of 6 times!
If the capacity of the air purifier is correct for the room to ensure at least 4x air filtrations per hour, and the filtration of the device is using H13 or H14 grade – the Covid/Infectious particles will be trapped & prevented from distribution.
Sars-CoV2 particles are a size of 100 nanometres in diameter, or 0.1 micron. The minimum requirement for a HEPA filter is to capture 99.97% of particulates as small as 0.3 microns, but actually they are nearly 100% effective with smaller size particles. The same goes for many other airborne illnesses such as the flu and the common cold, which are typically ranging between a micron size of 0.5 < 2 um and are also successfully trapped by a HEPA 14 filter.
Ok, what about preventing me from getting Hay-Fever and improving my Asthma?
Exposure to particulate matter (PM2.5) is a well-known risk factor in triggering and exacerbation of allergic airway diseases. Ironically, when we spend 80-90% of our time indoors we are exposing ourselves to these particulates such as dust, pet dander, pollen and even pollutants arising from our furniture and carpets!
An air purifier with HEPA filtration will capture these particulates, filtering them out of the air before you breathe it – meaning that your symptoms for Hay-Fever and Asthma will be vastly improved.
Testimonials speak for themselves. “I purchased the Zona 250 for my office as I heard from colleagues that it’s a very effective unit. To my pleasant surprise, within hours of turning on the unit my hay-fever symptoms were dramatically reduced. Wow! Powerful little machine”.
Where is the evidence?
It doesn’t take much to find a myriad of success stories for those who’ve implemented HEPA filtration, but here are 3 great case studies:
- NHS Addenbrookes – A hospital in Cambridgeshire, UK trialled the effectiveness of portable HEPA filtration units on 2 COVID ICU wards to determine whether they could help prevent the spread of the airborne SARS-CoV2 particles. The particulates in the air were measured over a 2 week period and whenever the air filtration unit was turned on, there was no trace of Covid Particles in the air as well as a complete removal of many other virus, bacteria and fungi particles. (check out this link)
- Windsor Federal Savings Bank – Since moving into their new office in February 2021 which included HEPA filtration by every workplace, the Connecticut-based bank hasn’t had a single instance of Covid transmission through the workplace, even with staff back on both hybrid and full-time schedules in the administrative offices and branch locations. (check out this link)
- The Hospice of St Francis – After implementing Zonitise portable air purification units to all areas of the London based care unit, the Hospice has stopped wearing face masks and reported zero cases of Covid whilst also stating that their staff and patients feel a lot more comfortable about working in the building given that the air feels cleaner.
Aside from preventing infections and improving respiratory conditions – what other benefits does an air purifier have?
- Helps remove odours and keeps your space smelling fresh
- Removes VOCs & Formaldehyde which cause eye, nose and throat irritation and can cause difficulty in breathing, headaches and nausea.
- Improves cognitive function and productive performance by filtering out the particulate matter that slows down oxygen flow
- Reduces staff absence and the associated downtime costs by keeping them healthy at work
- Improves the perception of your building and gives confidence to visitors that the air is pure
- Improves sleep quality
- Eliminates any harmful asbestos particles
- Removes harmful Radon from the air
- Can increase life expectancy
- Helps skin to stay healthy by capturing any toxins which trigger itchiness, acne and other uncomfortable skin conditions
Well it seems like air purifiers do work in general – but are there any other points we’re missing?
Remember – not all air purifiers are created equal. Despite the high efficiency of many HEPA filters, the housing designs of some air purifiers are not completely airtight which means that unfiltered air can pass around the HEPA filter through tiny openings, cracks, and space around the frame of the HEPA filter itself or between the frame and the purifier housing. In some cases, the actual efficiency of the whole air purifier design, with leakage considered is close to 80% of less.
There are some air purifier technologies which should be avoided. For instance, Air Ionisers, Ozone Generators & UV Light air purifiers. Many independent studies have found these methods are not effective at purification and can have detrimental effects on health such as causing heart disease and stunting lung development in children.
These links to our learning centre blogs will also help with other key points to consider when purchasing an air purifier:
- Do I need an air purifier?
- Why should I be worried about indoor air quality?
- How much does an air purifier cost?
- Which is the best air purifier?
At Zonitise, we’re a family business specialising in medical grade air filtration devices for all types of spaces – from your home to the office, hospital to hotels. You can check out our solutions on our website, or request a custom quote