According to the Environmental Protection Agency, indoor air may be up to 5 times more polluted than the air we breathe outdoors, which can lead to unhealthy environments for people working in offices.
There are different kinds of technology to clean indoor air, but the cleaning capacity and the type of impurities they clean varies, as do the economics of the purchase.
First, it helps to understand that there are three categories of things that might be removed from the air: particles (such as dust and smoke), microorganisms (such as germs or viruses) and molecules or gases (such as carbon dioxide, Volatile Organic Compounds,or formaldehyde).
A variety of filters are available that can capture particles and microorganisms. The most effective are known as HEPA filters. However, molecular air pollutants are far too small to be cleaned by any of the traditional filtration methods, not even by the best HEPA filters.
Molecular air cleaning is hard to do: it requires sophisticated technologies. There are only a handful of such techniques.
Only one, adsorption-based cleaning, can address all contaminants without generating any harmful byproducts.
Adsorption based molecular air cleaning was developed for use in mission critical settings, such as in spacecraft and submarines, where ventilation wasn’t possible, as well as for certain industrial processes. Over time, much was learned in these applications, and the technology evolved to become a practical and superior alternative to ventilation: instead of diluting contaminants, it actually removes them from the air. Only recently has adsorption based molecular air cleaning solution been made available for commercial use, to improve building health and energy efficiency in HVAC consumption.
Comparing Air Cleaning Technologies
Understanding the different cleaning and filtration methods helps in the selection of the technologies that help create the healthiest indoor air.
Here are a few molecular air cleaning and filtration technologies and various advantages of each technology.
Adsorption Air Cleaning
Adsorption air cleaning technology stands out as the most effective and comprehensive solution. It captures a wide range of contaminants, including VOC, formaldehyde, inorganics and perhaps most notably, CO2. Its practical implementation requires in-situ regeneration and an exhaust. This technique has only recently become available as a turn-key solution known as the HLR® system, provided by companies such as enVerid.
BPI – Bi-Polar Ionization
BPI uses energized ions that break down organic molecules. This technique is quite effective in reducing the levels of many VOCs and, according to some studies, killing certain microorganisms as well. In breaking down compounds from chemicals such as paints, solvents and pesticides, the solution may be worse than the problem, since some of the breakdown byproducts can be more toxic than the original offenders.
For that reason, this technology is yet to receive a nod from the ASHRAE. Also, BPI does not seem to have much impact on eliminating smaller molecules, like CO2 and formaldehyde, which means ventilation is still required. BPI is most effective as a specialized intervention for environments with very high levels of odors and fumes