A Detailed Overview of Air Purifiers

air purifier

At no other time in history have air purifiers been more important for good health than now. As our outdoor environment deteriorates so does our indoor environment. With tighter and more energy-efficient homes we have been able to regulate temperature control more effectively. At the same time, trapping more indoor air pollution than ever before. From common household uses and items like VOCs from cleaning agents and paint, cooking fumes, dust, pet dander and more. According to the EPA, the air inside your home can be five to ten times more pollutant than the air outside. This is a jaw-dropping consideration since the average American spends more than 90% of their time indoors.

So, this is where the use of air purifiers becomes a vital part of every home. You have decided that purchasing an air purifier is the right decision for you and your family. So, now where do you start? The selection of air purifiers is vast and everyone claims to have the best option. Price points are all over the map. Just like the selection and it can be easily overwhelming with just a simple Google search. So, where do you start? What is the best option?

Two Different Types of Air Purifiers: Passive and Active

Passive Air purification

Passive air purification is a process of moving contaminants in the air through a filter in order to collect them. Here are two examples of passive air purification.

HEPA Air Purifier

I would like to propose that this is actually air filtration even though most use the verbiage air purification. A High-Efficiency Particulate Arrestor is a very dense filter and or a very tight filter. This filtration device is very effective in removing particulate down to 0.03 or 0.05 microns. Mold for example is normally between 2-20 microns in size. Which is why Mold Remediation Professionals use HEPA filtered vacuum cleaners to remove mold.

When it comes to the use of HEPA air filtration to create a cleaner indoor air environment HEPA filtered machines are effective. The challenge is to draw all of the air in the airspace through the filter. In order to capture the particulates. Normally these HEPA filters themselves are rather small. Meaning that a limited amount of cubic air is filtered through the filtration device. Depending upon the size of the area you are trying to address; there would need to be several units in different locations of the property. You can also buy larger units with bigger filters which provide a larger volume of air that can be filtered. Hepa filtration units do need frequent maintenance such as filter replacement which can be rather costly.

Carbon Filter Air Purifier

Carbon filtering is much the same as HEPA filtration, but different because instead of filtering particulates it is filtering/absorbing gases or VOCs. They are rather effective. If the volume of air that is contaminated can be drawn through the filter at a large enough rate. To significantly reduce the gases in the air. Carbon filters are very effective at aiding in the removal of smoke odor in places such as restaurants or bars. As with the HEPA filter the carbon filter needs to be replaced frequently which is an ongoing investment. There are a number of machines that have both carbon and HEPA filters in the same unit. To address multiple contaminants at the same time.

Active Air Purification

Active air purification is using technology to release charged particles in the air space for purification:


There are multiple types of Ionization, but all essentially generate positive and negative ions into the air by the millions. Ionization causes nano-sized contaminants to stick to the ions clumping together. Thereby, becoming heavy enough that the particles then fall to the floor out of the breathable air space. These larger particles are then vacuumed or pulled into the HVAC filter.

Photo Catalytic Oxidation

This is one of the newest and most advanced technologies available. Similar technology has been used by NASA to purify surfaces and air space in the international space station. It is used by many petrol production facilities to reduce VOC’s. PCO produces a powerful yet environmentally friendly plasma of oxidizing agents that oxidize. Thereby, breaking down pollutants such as volatile organic compounds. This is done by using a titanium dioxide-coated metal plate. Which works along with a UV light to actually oxidize all kinds of chemical pollutions.

The titanium dioxide and UV light actually break down the molecular bonds that hold molecules of VOCs together. As biological contaminants move across or through the PCO cell they are actually destroyed. Pollutants out in the room are also destroyed by the same powerful oxidizing agents moving onto surfaces, furniture, carpeting, etc. PCO technology is also effective in reducing dangerous pathogens. The byproduct of PCO is simply carbon dioxide and water molecules which are completely safe.

Things to Consider Before Purchasing an Air Purifier

  • Type of Air Purifier – Choose either a passive or active purifier based upon your needs. At FSR we recommend active air purifiers.
  • Is the air purifier a combo unit – some air purifiers are combined with either heater and/or humidifiers.  Make sure to choose a unit with independent modes to enable the year-round use of the unit.
  • Area size for air purification – square footage is normally based on eight-foot ceilings
  • Air exchanges per hour (ACH) – how many times the air in the room will exchange in an hour.
  • Replacement Filters longevity – how many times per year do filters need to be replaced and costs per year

Air Purifier Placement

Okay, so now you have your air purifier where do you put it? It is more difficult to purify the air of a large room. Therefore, we recommend placing your air purifier in your bedroom approximately 6-10 feet from the headboard of the bed. With registers pointing at the bed for maximum breathing benefit.

Air Purifier Limitations

Air purifiers are not miracle workers but do make a big improvement in reducing allergens and other indoor irritants. The effects you feel from an air purifier vary; depending on your own sensitivity of responses to air irritants and the source of the irritation.