Visiting our health care practitioners should not be a risky activity. The air we breathe is filled with pathogens, viruses, spores, and molds. Pura Air™ ensures we eradicate risk at the molecular level by employing UV and medical grade HEPA filtration technology.
The reality is indoor air is trapped, often re-circulated and always full of contaminants. Increasing levels of these contaminants act as triggering mechanisms for a variation of diseases, such as COVID19 and asthma. We are all at risk of contracting and spreading viruses and bacteria, especially in busy public areas such as medical facilities, offices, stores, schools, museums and on public transport.
A source of concern in health-related fields are bio-aerosol clouds that form as a result of medical and dental procedures. The goal becomes capturing these airborne particulates and not only filtering them out but killing the viruses and other harmful bacteria before they find their way back into the air. This is where current filtration systems fall short.
Pura Air™ has developed both centralized and standalone medical-grade air purification systems to remediate and protect against all infectious and non-infectious airborne particulates. The Pura Air ™ patent-pending technology was designed by industry leaders across a variety of sectors, including medical, industrial clean air, mechanical contracting, as well as key research and development support from Signify (Philips Lighting).
With the help of industry leaders in industrial clean air applications, UV-C light, and healthcare mechanics, we determined the current systems on the market have various design and construction flaws that don’t maximize performance. We created a solution using proven, existing technologies and applied them to a dental and medical setting, eliminating these imperfections. Let us explain.
Current Limitations in Air Filtration
Building HVAC systems
Building HVAC systems are designed to deliver heating and cooling. They DO NOT “clean the space”. They do not use proper air distribution to minimize “dead zones”, they do not contain a good air change rate, nor do they contain rigorous air purification/filtration systems (i.e.: For Hospitals, Labs, Pharmaceutical Industry, Aerospace)
HVAC systems focus on economics, keeping energy costs to a minimum.
HVAC systems turn over air 2 – 5 times per hour, however they recirculate 80% of the air, spreading airborne particles.
Separate or portable air filtration systems
Many of the current systems on the market use the same principles in air filtration – a system of internal fans to pull the air through a series of filters that remove harmful airborne particulates. The air is then circulated back into the room or building.
How effective these systems are depends on numerous factors such as: air flow management, the volume of air being moved through the system, size of the room or facility needing to be filtered, how effective the filtration methods are (HEPA, carbon, ionized,etc.) and to what particulate size removal efficacy. Various combinations and methodologies exist in the portable systems currently in use.
One of the challenges becomes the need to remove these lethal particulates from the air we breathe. These micro particles require more work to be effectively caught and killed (influenza, SARS and Covid-19).
It is necessary to ask yourself: Is the unit providing enough airflow to account for static pressure losses? Is the method of filtration allowing for killing the smallest of particulates? Is it certified true HEPA filtration being used or an un-tested copycat filter? Are we addressing the specific risk such as source capture of aerosol’s? Length of UVC light exposure? Proper air change per hour and air flow calculations?
Through PURA Air’s own research, we have determined that the existing solutions do not have the technical features to ensure proper protection from harmful particulates.
Based on science and real-world applications, Pura Air ™ follows these guiding principles in our design solutions:
1. Accurate space air exchange rates for purifying both the localized and ambient air, with the clear directive to protect everyone from any airborne viruses being brought into the workplace.
2. A system that exposes all biological material introduced to the space. Because of this, the capture system becomes critical. See our Chief Technology Officers explain the difference between ‘ambient air capture’ and ‘source capture’.
- Dentistry: To accomplish this, the company has incorporated fume capture “high suction” source capture arms more typically used in laboratory and welding environments, and hood designs (transparent hoods providing shielded protection, while still not limiting visual operation) proven to be effective in those challenging environments.
- Other Medical/Commercial: No difference, other than no need for high suction arms, if local generation of aerosols is not present within space.
3. System fans designed with ECM motors speed control feature, provides fan speed manipulation, essential to be able to ramp up fans when filters are loading while ensuring that desired minimum air change rate is maintained.
4. The centralized system not only captures airborne particulate down to a HEPA filtration level, but it kills any viruses first. To achieve “high standard” indoor air quality, air purification will contain following:
- UV Filtration Chamber
UV-C lighting has the power to disinfect air, surfaces and water. All bacteria and viruses tested to date respond to UV-C radiation. Signify has been at the forefront of UV technology for many years and has a proven track record of developing innovative UV-C products and applications.
This stage of the system is used for sterilizing up to 99.9% of airborne bio-contaminants in a single pass.
Learn about UV Technology from Signify here
- MERV 8 Pre-filter & odor control chamber: necessary pre-filter to the HEPA filtration chamber, as well as carbon filter to scrub the air of odours, chemicals, and volatile organic compounds (VOC’s). The addition of Cobalt in the PCO matrix boosts the efficiency of the catalyst active sites to ensure complete destruction of odorous contaminants, which is not the case with other conventional PCO units being sold.
- HEPA chamber: the medical grade HEPA filter captures all particulate down to 99.99% @ 0.3 µm. Achieving this filtration level is possible with use of scan tested and certified HEPA Filters to stated filtration level. Increased particulate filtration efficiency is possible through a combination of certified leak testing, and size. This explanation from NASA dated May 2016 explains:
“The concept of the MPPS is applicable in this range and is typically taken to be the near minimum efficiency point. The MPPS for typical HEPA filters varies from 200 to 300 nm, depending on flow rate. The key implication to emphasize is that HEPA filters are nearly 100% efficient at capturing the spectrum of particles down to the very smallest airborne particles. Small changes in flow velocities through the media result in large changes in particle penetration through the filter. Particle penetration (P) is defined simply as the number of particles crossing the filter divided by the number of particles incident on the filter and is related to overall efficiency (ET) as P = 1 – ET. 9 As a rule of thumb, reducing the velocity by half not only reduces the pressure drop by half but also decreases particle penetration through the filter media by nearly an order of magnitude. This is illustrated in figure 4 where decreasing the velocity by three-fourths reduces the particle penetration over three orders of magnitude with a corresponding efficiency increase from 99.998% to 99.99998%. In other words, a simple HEPA-rated filter will perform as an ULPA-rated or better filter by simply lowering the flow velocity through the media.”
Submicron and Nanoparticulate Matter Removal by HEPA-Rated Media Filters and Packed Beds of Granular Materials
- Pura Air Purification has chosen to use the 24” x 24” nominal size face dimension in order to achieve a lower face velocity than the product’s top line specification. Our face velocity will be in the 300-375 FPM range, much lower than the maximum specified face velocity of 500 FPM. We feel this is prudent towards ensuring the highest possible (while being practical) efficiency.The specified HEPA filters are Scan Tested ( 99.99%) (A) Acceptance Level. From AAF, the specified Product – the AAF ASTROCEL HCX in size 24X24X11-1/2 – the minimum accepted tolerance for this product is 99.97% at 0.3 microns, however it is tested higher at 99.99% at .3 microns as a level of redundancy. This efficiency standard is in line with most air scrubbers on the market using a True HEPA. This is important because most brands of HEPA filers claim 99.97% @ 0.3 microns, but are not Scan Tested.
- This is where layering the methodologies is important. A UV – C chamber alone is log 1, 90% reduction. HEPA alone, not scan tested, is a minimum 99.97% reduction both at .3 microns. By making key product choices, and moving the air at the right velocity through these stages, ensures we get to 99.99% reduction at 0.3 microns. We have engineered each stage of filtration to work to maximum efficiency individually, then together. Infection control is additive, so layering each step will reduce the risk.
5. Safety and assurance that the air being returned to the space has been adequately scrubbed. Differential pressure sensors at each filter will provide real time feedback and signal the end user when maintenance is required.
Pura Air ™ has worked to re-engineer solutions that mitigate the flaws in design, construction and proper science in air filtration by using industrial tested and true practices and applying these solutions to medical and dental uses. We believe our germicidal ‘kill chamber’ will allow for safer, cleaner air for all who work and visit the Pura Air ™ purified space.