HEPA filters and hand dryers, what else do we need?
HEPA filters are a good way to remove harmful particles from a room. It is not by chance that this air filtering system has been used in hospital operating rooms for many years. Quite the opposite, they use it for it’s more than proven effectiveness. In our post "Are HEPA filters a safe solution for COVID-19?" we valued the efficiency of this type of particle filters. But, can we do more than just filter the air with HEPA filters? The answer is yes. A good option would be to add a negative ion (anion) generator.
Air ionization has been in use for decades and is widely applied in air purifiers, both industrial and domestic. It is a very safe technology for humans. It is the same technology that is used in hair dryers to protect hair from pollution, by neutralizing air pollution, in addition to reducing drying time, reducing hair dehydration and also avoiding frizz. But, can we say that an ionizer can "kill" viruses and bacteria? The answer is, again, yes, although there is always a 'but' ...
"Ionic hair dryers have a negative ion generator that breaks down water molecules facilitating both quick drying and hair hydration, as well as protecting hair from pollution."
Negative ions (anions) act in two different ways that complement each other. On the one hand, anions have the ability to severely damage the DNA or RNA (depending on the type of microorganism) of microscopic organisms and inactivate them. On the other hand, they also have the ability to attract polluting particles that are in the air (viruses, bacteria, fungi, dust, smoke, etc.), so that they become denser than the air itself, fall under gravity and are deposited on the surfaces of the room, from where they will be removed with the usual cleaning systems. With this combined action we achieve that part of the pathogens in the air are brought to the ground and some of them are also inactivated, hence losing their harmful functions to our health.
The article "The bactericidal effect of an ionizer under low concentration of ozone" talks, in much more detail, about the bactericidal effect of negative ion generators. This article describes the tests carried out with standard ionizers and concludes that these devices have the ability to “kill” (“deactivate” in scientific jargon) viruses and bacteria.
Moreover, the amount of ions generated depends on the size of the mentioned generator. In a hair dryer, the ionizer is somewhat smaller than those installed in centralized air conditioning systems or in hand dryers, which are larger. However, and regardless of size, what is clear is that these disinfection systems are capable of eliminating many of the pathogens in the environment, making that the air that comes out of purifiers, air conditioners, hair dryers or Electric hand dryers has far fewer pathogens than the air they absorb. Therefore, we can confirm that the use of ionizers, inside all these devices, contributes significantly to the cleaning and purification of the air.
“The use of ionizers in hand dryers, air conditioners or air purifiers contributes to the cleaning and purification of the air”
The Mediclinics Ion Hygienic system uses this negative ion (anion) technology and is available in the Dualflow Plus, Machflow and Speedflow Plus hand dryers. The anion generator is fully complementary and compatible with the HEPA filter medium and, for this reason, the versions of electric hand dryers with Ion Hygienic also feature a filter with HEPA filter medium.
In the state of California (USA), air purifying products must pass further tests than the usual ones and be registered on a list of the California Air Resources Board (CARB). Hand dryers that incorporate ionizers, despite not being actual air purifiers, as they have a component that purifies it, must pass the tests requested by CARB and be registered in their listings as air purifiers (Air Cleaning Devices). Mediclinics eco-fast hand dryers (Dualflow Plus, Machflow and Speedflow) have been certified as air purifiers by CARB and as such appear in their LISTINGS.
"The negative ion (anions) generator is additional to the HEPA filter medium"
Therefore, we can say that ionizers, technologically speaking, are a good solution for air purification. If, in addition, they are used together with an HEPA filter medium, the combination cannot be more satisfactory in terms of obtaining pure air, free of impurities and microorganisms, especially in closed rooms with little ventilation, such as public bathrooms.
To conclude, we would like to mention that currently, the BabyMedi changing station series also incorporate Ion Hygienic technology which, together with the Biocote® antimicrobial additive that they have incorporated, makes these baby changing stations the most hygienic in the market. We are aware of the importance of this innovation on ionizers applied to baby changing stations for public use. For this reason, we highly recommend you to read our next post that will deal with this topic in depth.