Understanding air filtration and UV disinfection in a medical environment

Health Europa reports on why UV purification is the most effective air disinfection method for medical, commercial and residential environments.

Evidence has accumulated over the years that following the standard guidelines and codes for designing healthcare facility ventilation systems is far from sufficient to ensure a sterile environment. Sterility is generally defined as 6 log (99.9999%) reduction of a population of microorganisms. This means that as little as one microorganism in a million is expected to survive after disinfection.

Traditional air filtration with high-efficiency particulate air (HEPA) filters or ultra-low penetration air (ULPA) filters have been widely adopted in the ventilation systems of hospitals, labs, and clinics, to control airborne pathogens. However, multiple studies have demonstrated that despite the use of such high-end filters, viral and bacterial airborne contamination are still ubiquitous in these ventilation systems. 

The most common explanation for underperforming filters often points to the filter rack seal joint’s bypass, filter puncture leakage, and poor general installation or maintenance. Although all these points remain valid and can always be improved, the physical cause is rooted in the fundamental fact that all filters show a significant drop in their capture efficiency for a certain range of particulate sizes – these can include both particles which are too small to be captured by interception and impaction and those which are too large to be removed via electrostatic and diffusion. This is simply a straightforward consequence of the fundamental principles of filtration physics. […]

Read more on Health Europe website.

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Using Sanuvox UVC technology to reduce the propagation of SARS-CoV-2 virus

Using Sanuvox UVC technology to reduce the propagation of SARS-CoV-2 virus

  • UVC irradiation (254 nm) is known for its germicidal properties. By disrupting their nucleic acids (DNA/RNA), it inactivates the reproductive capability of biological pathogens (molds, viruses, bacteria).1, 2

  • Sanuvox in-duct units have been demonstrated to be up to 99,97% effective at inactivating viruses and bacteria in the air in a study conducted by the EPA and Homeland Security 3. Bacteria and virus tested in the study (B.atrophaeus, S.marescens, MS2) are known to be more resistant to UVC than SARS-CoV-2 virus. 4,5
  • Many engineering and health agencies (ASHRAE, REHVA, CDC) now recognize that airborne transmission plays a major role in the propagation of SARS-CoV-2, the virus responsible for COVID-19. These agencies also recommend using UVGI as an effective method to mitigate the spread of the virus in indoor spaces. 6, 7, 8, 9
  • Because Sanuvox units are specified according to HVAC systems parameters, adequate UV output power is calculated using our proprietary software. As such, patented Biowall units can achieve the recommended 99% disinfection per pass regardless of air velocity.
 

1 https://www.fda.gov/medical-devices/coronavirus-covid-19-and-medical-devices/uv-lights-and-lamps-ultraviolet-c-radiation-disinfection-and-coronavirus

2 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2789813/

3 https://cfpub.epa.gov/si/si_public_record_report.cfm?Lab=NHSRC&address=nhsrc/&dirEntryId=154947

https://www.springer.com/gp/book/9783642019982

5 https://www.researchgate.net/publication/339887436_2020_COVID-19_Coronavirus_Ultraviolet_Susceptibility

https://www.ashrae.org/about/news/2021/ashrae-epidemic-task-force-releases-updated-airborne-transmission-guidance

7 https://www.cdc.gov/coronavirus/2019-ncov/science/science-briefs/scientific-brief-sars-cov-2.html

https://www.rehva.eu/fileadmin/user_upload/REHVA_COVID-19_guidance_document_V4_09122020.pdf

9 https://www.ashrae.org/technical-resources/filtration-disinfection

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Sanuvox UV air purifiers capabilities against viruses

Sanuvox UV air purifiers capabilities against viruses

Sanuvox corporation, a North American leader in UV disinfection of air and surfaces, would like to warn people tempted to purchase air purifiers or other devices against potential claims that would find themselves misleading.

UV air purifiers installed in the HVAC system, with an adequate germicidal dosage sized for the air flow, will destroy airborne viruses, but cannot guarantee anyone from becoming infected.

Air purifiers inside HVAC cannot disinfect frequently touched surfaces such as door handles and light switches, which are common disease transmission path. So good hygiene practice and frequent wash of hands continue to be the safest way to protect ourselves against any airborne or surface contaminants that can be introduced by other occupants and dispersed by the HVAC system in the house.

In other words, a powerful UVC air purifier can reduce the possibility of spreading the contaminants through the HVAC system, but it does not eliminate the necessity of safe hygiene practices.

 
Because the susceptibility to germicidal UV of any microorganism is determined by its genome sequence, the germicidal UV dose required to kill the CoVid-19 is practically the same as for the SARS-CoV (2003) within less than 1.6% variance.
 

For additional technical information regarding Covid-19, please visit https://bit.ly/38t12Mo.

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Purifying Air in Kennels & Veterinarian Centers

Purifying Air in Kennels and Veterinarian Centers

Illness among animals especially dogs can be significantly higher when many of them are boarded within close proximity, or kept within the same room or building. Airborne illnesses can easily be transmitted from one animal to another. Odors may cause issues when they migrate to other areas and affect staff and visitors.

Sanuvox UV systems are the ideal solution for destroying airborne viruses and bacteria, as well as reducing the concentration of unpleasant odors, such as ammonia produced by animals in kennels, shelters, pet stores and veterinarian clinics. Its proprietary system eradicates biological contaminants (bacteria, viruses, germs and allergens), and destroys chemicals and biological odors.

THE EQUIPMENT

Multiple application UV systems can be used for both stand-alone and duct-mount installations.

As stand-alone units, the P900 is equipped with an 80 cfm blower, the Sanuvair® S300 with a 300 cfm blower, and the Sanuvair® S1000 with a 1000 cfm blower. Sanuvair® S300 and S1000 also come with filters to capture particulates (pet hair, etc.). A dual zone UV-C/UV-V lamp is standard. An “adjustable” oxidizing lamp is available.

As an in-duct unit, the Quattro is installed parallel to the airflow and includes four UV-C/UV-V lamps, each with a one-inch section of oxidizing UV-V. Two of the lamp’s oxidizing sections are covered with removable foil, allowing for increased oxidation if necessary.

Typical installations:

OPERATING THE EQUIPMENT

Each unit treats the air through recirculation in two ways:
1. The Germicidal UV-C lamp portion destroys airborne biological contaminants (viruses, mold,
bacteria.)
2. The Oxidizing UV-V lamp portion reduces airborne chemical contaminants and VOCs through
photo-oxidation.

PROCESS ON BIOLOGICAL AND CHEMICAL CONTAMINANTS

1-ACTIVATION PHASE:  H2O + O* –> OH* +OH*
Ultraviolet photon energy (170-220nm) is emitted from a high-intensity source to decompose (break down) oxygen molecules into activated monoatomic oxygen. The rate of production or effectiveness of this process depends on the wavelength and intensity of its source.

2-REACTION PHASE: OH*+P –> POH
The activated oxygen atoms (O*) are then mixed in the airstream; the process will react with any compound containing carbon-hydrogen or sulfur, reducing them by successive oxidation to odorless and harmless by-products. If airborne contaminants are outnumbered by the activated oxygen atoms, then there will be formation of residual ozone (O3) which will occur following the oxidation of normal oxygen molecules (02).

3- NEUTRALISATION PHASE: (also germicidal)  O3+UV(C) –> O2+O*: O+O –> O2

CHEMICAL DECOMPOSITION:
Ammonia NH3+OH* –> N2 + H2O

WHERE TO INSTALL

Many buildings and facilities can be equipped with either the stand-alone disinfection units or the in-duct unit, like kennels, pet boarding and animal shelters, laboratories, veterinarian centers, and zoos and pet stores.

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Sterilizing Air in Facilities

Sterilizing Air in Facilities

New buildings are built tighter to save energy, while older buildings are implementing new measures to reduce heating and cooling loss. Reduced fresh air also prevents dilution of contaminated air resulting in an increase of contaminants as they are now trapped inside and are continually recirculated throughout the space.

Indoor Air Quality (IAQ) applications in hospitals, schools, commercial buildings and offices vary. From Hospital Acquired Infection (HAls), sick building syndrome, absenteeism and work place productivity, Indoor Air Quality influences these facilities in many differents ways.

When the objective is to eliminate up to 99.9999% of airborne bio-contaminants, including viruses and bacteria that circulate through the ventilation system without increasing the pressure drop resulting from high efficiency filtration, Sanuvox offers the right solution with its high efficiency patented air purification system.

THE EQUIPMENT

The BioWall air purification unit is installed in the ventilation duct parallel to the airflow, allowing sufficient contact time that is required for airborne sterilization. The UV-C intensity of each lamp can be measured in “realtime” with an optional UV-C sensor, ensuring the required inactivation intensity will be delivered to the contaminant.

OPERATING THE EQUIPMENT

To create the sterilization chamber in the existing duct (up to 5 feet deep per unit), the walls are covered with an aluminum reflective material. The proprietary sterilization sizing calculations take into account: air velocity, dimensions of the duct, the UV lethal dose needed to sterilize the microorganism for the desired inactivation rate. The sizing calculations will determine the number and length of the BioWall unit(s) required. The optional UV-C sensor will guarantee that the UV-C emitted from the lamp will exceed the amount of UV-C that is required at all times.

UVC GERMICIDAL PRINCIPLE

The 254nm UV-C germicidal wavelength has been used for decades for sterilization and its effect on microorganisms is well documented. UV germicidal process inactivates microorganisms by damaging their DNA structure, making it incapable of reproducing. The germicidal efficiency can deliver virtually a 100% disinfection rate. The system can achieve exceptionally high disinfection rates as a result of the BioWall unit being mounted parallel to the airflow and the desired intensity is sized for each particular application.

WHERE TO INSTALL

Many buildings and facilities can be equipped with the BioWall unit, like hospitals, private clinics, veterinary clinics, as well as fertility centers. It can also be installed in schools, universities, offices towers and commercial buildings.

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Purifying Air & Destroying Airborne Bio-Contaminants

Purifying Air and Destroying Airborne Bio-Contaminants

It is not uncommon for outside contaminants, including odors and allergens, to find their way migrating into a building. Restaurant odors, manufacturing off-gassing, diesel fumes from idling trucks, and even jet fuel from helipads can be pulled into the make-up air and distributed throughout the HVAC system and building.

Sanuvox Technologies line of in-duct UV air purification systems are the ideal solution for these often troublesome issues. Sanuvox offers exceptionally cost-effective systems that can address IAQ issues that filters and absorption media cannot. The proprietary system eradicates biological contaminants such as mold, bacteria, viruses, germs and allergens; reduces chemicals, VOCs and biological odors. Installed PARALLEL to the air-stream results in greater « dwell time » between the air and the UV lamps.

THE EQUIPMENT

The duct-mounted units are installed in the return or supply side of the HVAC system parallel to the airflow, and are supplied with multiple germicidal UV-C lamps, each with a section of oxidizing UV-V that can be adjusted (covered or removed) depending on the concentration of odors.

Typical installation on the HVAC return side:

OPERATING THE EQUIPMENT

The UV lamps disinfect the recirculating air in two ways:
1. The oxidizing UV-V section of the lamp reduces the chemical components in the air through photo-oxidation. The selected units are designed to be “dosed” on site according to the need.
2. The germicidal UV-C section destroys airborne biological contaminants (viruses, bacteria, mold).

PROCESS ON BIOLOGICAL AND CHEMICAL CONTAMINANTS

1- ACTIVATION PHASE:   H2O + O* –> OH* +OH*
The ultraviolet photon energy (170-220nm) is emitted from a high-intensity source to decompose (break-down) oxygen molecules into activated monoatomic oxygen. The rate of production or effectiveness of this process depends on the wavelength and intensity of its source.

2- REACTION PHASE:    OH*+ P –> POH
The activated oxygen atoms (O*) are then mixed in the airstream; the process will react with any compound containing carbon-hydrogen or sulfur, reducing them by successive oxidation to odorless and harmless by-products. If airborne contaminants are outnumbered by the activated oxygen atoms, then there will be formation of residual ozone (O3), which will occur following the oxidation of normal oxygen molecules (02).

3- NEUTRALISATION PHASE: (also germicidal)  O3+UV(C) –> O2+O*: O+O –> O2

CHEMICAL DECOMPOSITION

Formaldehyde CH2O + OH* –> CO2 + H2O

Ammonia NH3 + OH* –> N2 + H2O

Styrene C8H8 + OH* –> CO2 + H2O

Mercaptans H2S + OH* –> SO2+ H2O

WHERE TO INSTALL

Many buildings and facilities can be equipped with these in-duct units, like buildings near airports and helipads, buildings with adjoining warehouse (diesel), printing shops, restaurants, mechanical workshops, and crematoriums.

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