As owners and technicians in the Indoor Air Quality industry, we have decades of experience in the field. However, when it comes to the health and safety of our family, this includes you, experience alone is not quite enough. We have combed through hours of technical information, research studies, and surveys relating to various methods used in air filtration and purification, and we have made careful evaluations of the pros and cons of each technique.
We will be continually updating this page regarding various technical data we believe is pertinent to air purification concerns, as well as the risks and health benefits of each method we have chosen to employ.
We made sure we were well informed before exposing our own homes and businesses to potentially harmful methods and devices being sold as "purification" aids, and we want you to be informed as well!
More content soon!
(The effect of surface charge, negative and bipolar ionization on the deposition of airborne bacteria-full title)
This study concludes that Bipolar Ionization has an effect of significantly decreasing airborn bacteria deposits on surfaces. This is in major part due to the fact that the presence of positive and negative ions greatly reduced the presence of static electricity which attracts and traps pathogens and other harmful microorganisms.
"Allen et al. (2006) demonstrated that moving an item carrying a static charge into close proximity of hospital patients could induce an electric field surrounding the patient, causing an excess of potentially harmful airborne micro‐organisms to be attracted towards them. The results of this study clearly support the notion that electrostatic attraction can be a significant force affecting the deposition of airborne bacteria"
The article also points out the various ways pathogens can be aerosolized especially in hospital settings. Aerosols and airborn particulate are drastically reduced by bipolar Ionization.
"The results of this study suggest that similar ionization‐type engineering controls could be employed to minimize surface charge in hospital settings, which may help reduce the potential for fomitic disease transmission because of the deposition of bioaerosols."
Gabbay et al. (1990) noted a 40–50% reduction in microbial air pollution after employing a 13·5 kV (polarity unspecified) corona‐type ion generator every second week in a dental clinic. Similar types of studies have been conducted for nonbiological particles in the semiconductor industry
Indoor Air 2005; 15: 235-245
Center for Health Related Aersol Studies, Department of Environmental Health, University of Cincinnati
S.A. Grinshpun, G. Mainelis, M. Trunov, A. Adhikari, T. Reponen, K. Willeke
This study tested five different sized ionic purifiers (two wearable and three stationary) in a controlled environment and discovered a number of groundbreaking insights.
"The removal efficiency of the more powerful of the two wearable ionic purifiers reached about 50% after 15 min and almost 100% after 1.5 hours of continuous operation in the chamber under calm air conditions. In the absence of external ventilation, air mixing, especially vigorous one (900 cfm), enhanced the air cleaning effect. Similar results were obtained when the manikin [inside the test chamber] was placed inside a partial enclosure that simulated an aircraft seating configuration. All three Stationary ionic air purifiers tested in this study were found capable of reducing the aerosol concentration in a confined indoor space. The most powerful stationary unit demonstrated an extremely high particle removal efficiency that increased sharply to almost 90% within 5-6 min, reaching about 100% within 10-12 min for all particle sizes (0.3-3um) tested in the chamber."
"Strategies developed for protecting building environments from deliberately used aerosol agents require efficient air filtration and air cleaning systems [National Institute for Occupational Safety and Health (NIOSH), 2003]...Among various mechanisms, the emission of ions, also referred to as air ionization, has shown considerable promise. Emission of bipolar ions enhances the agglomeration of smaller particles into larger ones, which then gravitationally settle and thereby purify the air...The physical and biological effects of small air ions on indoor air quality as well as various health benefits and implications of air ionization have been discussed in the literature (Daniell et al., 1991; Kondrashova et al., 2000; Krueger and Reed, 1976; Soyka and Edmonds, 1977; Van Veldhuizen, 2000; Wehner, 1987). The ion emitters, which meet health standards (e.g. by not generating ozone above the established thresholds), have been incorporated in commercial air purification devices that utilize either bipolar or unipolar ion emission."
"The measurement data showed that the concentration of 2-3 um NaCl particles in the test chamber naturally decreased by 50% in about 2 hours, while for 1-um particles of NaCl and P. fluorescens cells, the 50% decrease took over 10 hours. The concentration of 0.3-0.4-um particles of NaCl showed <10%decrease during a 10 hour period. Mosto of our experiments involving ionic air purifiers were conducted within much shorter time periods (1-3h), because our pilot data showed taht the air ionization can significantly reduce the aerosol concentration during about an hour (Grinshpun et al., 2001)."
The study goes on to detail that the performance of each purifier increases exponentially with time and added airflow.
Application of corona discharge-generated air ions for filtration of aerosolized virus and inactivation of filtered virus, Journal of Aerosol Science 107 (2017) 31–40
This article covers a great amount of detailed information regarding the effectiveness of ozone, unipolar, and bipolar ionization in removing bacteria, virus, and particulate. It concludes that Bipolar ionization is quantifiably the best method tested.
"Although airborne particles can be removed by filters, indoor bioaerosols accumulate in large quantities on the filters, where they can multiply under certain conditions, especially if high amounts of moisture are present on the filters. Moreover, the organic or inorganic materials deposited on the filter media after air filtration contribute to microbial growth (Verdenelli, Cecchini, Orpianesi, Dadea, & Cresci, 2003). This inevitably leads to a decreased filter efficiency and, probably, to the deterioration of the filters and the eventual release of microorganisms."
"Captured virus particles were detached from the filter by sonication, and their antiviral efficiency due to air ions was calculated by counting the plaque-forming units. The antiviral efficiency increased with ion exposure time and ion concentration. When the concentration of positive air ions was 107 ions/cm3, the antiviral efficiencies were 46.1, 78.8, and 83.7% with exposure times of 15, 30, and 45 min, respectively. When the ionizer was operated in a bipolar mode, the number concentrations of positive and negative ions were 6.6×106 and 3.4×106 ions/cm3, respectively, and the antiviral efficiencies were 64.3, 89.1, and 97.4% with exposure times of 15, 30, and 45 min, respectively. As a quantitative parameter for the performance evaluation of air ions, the susceptibility constant of bacteriophage MS2 to positive, negative, bipolar air ions was calculated as 5.5×10−3, 5.4×10−3 and 9.5×10−3, respectively. These susceptibility constants showed bipolar ion treatment was more effective about 1.7 times than unipolar ion treatment."
"Ozone was sampled at 90 mm downstream of the ionizer. The ozone concentration was 2~10 ppb when unipolar air ions were generated. When bipolar air ions were generated, the ozone concentration a little increased to 30 ppb. To study the effect of ozone on antiviral efficiency, we carried out additional experiments. After the ionizer was operated in a bipolar mode, all of the positive and negative air ions were eliminated using an ion trap with 20 V of applied voltage. Then the remaining ozone of 30 ppb concentration was carried by air flow to the test duct. When the virus particles captured in a filter were exposed to the ozone flow for 45 minutes, it was found that the antiviral efficiency of ozone was 4.52% which was much lower than that of bipolar ions (please remind that the antiviral efficiency was 96.4%, when the virus particles were exposed to both the ozone and bipolar ions for 45 minutes). De Mik and De Groot (1977) also observed that airborne phi X174 phage kept biological activity at an ozone concentration of 40 ppb and a contact time of 30 min."
This informative article has excellent information regarding both the hazards of poor air quality and the benefits of negative ions. This informative article has excellent information regarding both the hazards of poor air quality and the benefits of negative ions.
"Long-term exposure to particulate pollution – tiny particles smaller than 10 microns (a human hair is 70 microns wide) – is known to increase illness and death rates from lung cancer, chronic obstructive pulmonary disease and emphysema."
The bipolar ions generated by the o2 Defense custom series of ionizers cause these micro-particles to become positively and negatively charged, essentially turning them into magnets that bond together. Once bonded and larger they are then lowered from the typical breathing zone and eventually trapped in standard air filters.
"Research conducted in the last decade has begun to support the view that negative ions have a net positive effect on health.
One of the most tantalizing hints regarding negative ions and health surfaced when German researchers discovered a link between catecholamine regulation and lifespan after depriving experimental animals of negative ions. First, researchers at the Goldstein and Lewin Dept. of Medical Research in Stahnsdorf, Germany isolated mice and rats in air-tight, sealed acrylic cases. Next, they filtered the ambient air to remove all negative ions from the sealed cases. Their research led to the discovery that a prolonged deficiency of negative ions led to an accelerated rate of death for the experimental animals. Examination of the animals led researchers to conclude that the results ‘strongly suggest that animal death is related to disturbances in neurohormonal regulation and pituitary insufficiency. (23)
Researchers at the Russian Academy of Sciences in Moscow discovered that negative ions are able to help protect the body from induced physical stress. When the researchers immobilized rats and exposed them to negatively charged air ions they discovered that the ions prevented the development of pathological changes characteristic of acute stress that are observed in untreated rats. The protective action of negative air ions was observed in all the experimental animals independently of their types of behavior. (24)
British researchers at the Centre for Sport and Exercise Sciences in Liverpool exposed male subjects to negative ions and measured physiological responses, including body temperature, heart rate and respiration, while at rest and during exercise. Negative ions were found to significantly improve all physiological states, particularly during rest. Most important was the finding that negative ions are “biologically active and that they do affect the body’s circadian rhythmicity.” (25)
Another clue to the role of negative ions in health comes from Russian research conducted at the Institute of Theoretical and Experimental Biophysics of the Russian Academy of Sciences, in Pushchino, Russia. Researchers found that exposure to negative ions increased levels of the protective antioxidant enzyme superoxide dismutase (SOD) in mammalian erythrocytes. The researchers also discovered minute amounts of H2O2 (hydrogen peroxide), writing, “The primary physiochemical mechanism of beneficial biological action of negative air ions is suggested to be related to the stimulation of superoxide dismutase activity by micromolar concentrations of H2O2 (hydrogen peroxide).”