PREVENTION: The only CURE (for Corona Virus)

With the world reeling with the Health Emergency, and scientists scampering to invent cures to the novel corona virus infecting humans across the globe, our only CURE, currently, is PREVENTION.

While we may follow suggested hygiene practices ie. avoid crowded / public areas, one of the critical factor of contamination control is the hygiene of the

“Respiratory System of the Buildings” – the HVAC systems.

In this article, we are sharing the sustainable, energy efficient solutions to eliminate microbial contamination within indoor spaces through the HVAC system and in-room solutions.

Outline of this article:

· Airborne Transmission & Contamination – an introduction

· Contamination through HVAC System

· Solution 1: Microbe elimination in HVAC Systems

· Solution 2: Microbe elimination at indoor spaces

· How Au Pure can assist

CONTAMINATION: What you need to know:

Airborne Transmission & Contamination:

The air can also play a major role in the transmission and dispersal of microorganisms, and building HVAC systems have been found to be a transport mechanism.

One cough can produce over 3000 droplet nuclei, and sneezing generates tens of thousands droplet nuclei, which can spread to individuals up to 10 feet away (1) . These small, infectious

droplets nuclei, generally less than 5 μm or less, can remain suspended in the air and disseminated by air currents to be inhaled by a susceptible host.

The HVAC Systems are the most common transmitters and in many cases, incubators of

microbial contamination. With large volumes of air handled through wide temperature and humidity spectrum, flowing through a large surface area of ducts, cooling coils, etc, HVAC Systems can become perfect haven for microbial deposition and proliferation if not maintained and controlled well.

According to the EPA, “pollutants in our indoor environment can increase the risk of illness.”

There is growing scientific and anecdotal evidence that rank indoor air pollution as an important environmental health problem.

Even well-run buildings can experience episodes of poor indoor air quality that can significantly influence rates of respiratory disease, allergy and asthma symptoms and sick building symptoms.

Contamination through HVAC Systems

HVAC coils and drain pans present a viable environment for growth of bacteria and mold. The EPA and World Health Organization are just two organizations that have identified a building’s mechanical system as a source of pollutants and microbial contamination.

According to the World Health Organization (WHO), approximately 30% of all commercial buildings have significant IAQ problems, and ventilation systems are implicated in the spread of infection and pollutants.

The Microbiology of HVAC Biofilm

So what’s going on in the HVAC system?

Air conditioning coils are the source of accumulation of biofilm that adheres to the fins of the coil. Biofilms are composed of different microorganisms adhering to surfaces and producing polysaccharides, proteins and nucleic acids. This material allows the biofilm to stick together and develop attached communities. They are attached primarily to the coils and drain pans.

Biofilms also provide protection to the microorganisms from penetration of outside agents such as the antimicrobial agents that facility managers may use to try to destroy them.

The biofilms themselves give off products of metabolism known as VOCs and microbial volatile organic compounds (MVOCs), which have been found to play a major role in Sick Building Syndrome, eliciting building occupant complaints that range from irritation, watery eyes and headaches, to more severe allergy and asthma responses.

In addition, many of the biofilm organisms growing on the coil and in drain pans of HVAC systems are known opportunistic organisms causing infections.

SOLUTION 1:

Microbe elimination in HVAC System: 99%+ elimination

The UVC treatments in the Cooling coils provide an effective solution to prevent legionella formation, and other condensation while eliminating the need for chemical based maintenance routines.

With the proper intensity and exposure time, UVC is effective at destroying or

inactivating many microorganisms.(2-12)

In buildings requiring general air cleaning and where there are four to six air changes per hour, UVC lamp systems installed in the air handlers can reduce contaminant levels below that which affects most people. Where a high level of infection control is needed for hospital and medical environments, germicidal UVC can successfully deliver contaminant destruction rates of over 99%, when properly applied in combination with high air exchange rates of typically 15-20 air changes per hour or more.

The following illustration shows the Kill rate for the SARS Corona Virus (affecting humans) and similar test results are available for porcine corona virus and other microbial contaminations.

With a single pass, the kill rate is 99% and we can achieve over 99.9% kill rate in subsequent passes.

© Photo Credit: Steril-Aire

The treatment significantly lowers the number of harmful microbes in the occupied space, dramatically reducing the potential spread of the virus.

How UVC Works

Ultraviolet germicidal irradiation (UVGI) is a sterilization method that utilizes ultraviolet (UV) energy at a wave length of 253.7 nm to break down microorganisms or inactivate viral, bacterial, and fungal species.

UVC irradiation alters the molecular bonds within the ability of DNA of a microorganism, thereby destroying them, rendering them harmless or prohibiting growth and reproduction.

Energy Efficient Solution

While allowing cleaner & more fresher air, the installed UVC Emitters will

· Lower HVAC operational costs by improving heat transfer and increasing net cooling capacity

· Continuously clean coils, drain pans, plenums and ducts, reducing or eliminating costly cleaning programs and the use of harmful chemicals and disinfectants

· Improve general IAQ for better productivity and less absenteeism

SOLUTION 2:

Microbe Elimination within Indoor Spaces

In addition to the UVC used either at Cooling coils or return ducts (in absence of cooling coil treatments), the complimenting technology to help fight the microbes at the source includes, Bipolar Ionization.

Bipolar Ions, like nature’s air-scrubbers, disperse into the occupied space through the duct system, proactively attacking airborne contaminants where they cause the most problems for occupants.

This installation is safe, low maintenance, easy-to-install, energy efficient, and highly effective on pollutants such as particulate matter, bacteria, viruses, mold spores, odors, and VOCs.

What Are Oxygen Ions?

Ions are molecules or atoms that contain an electrical charge and exist in nature in various sizes. Small ions only last between 30 and 300 seconds before losing their charge, but are extremely active.

Small ion densities range from 900 to 1,100 negative ions and 1,000 to 1,200 positive ions per cubic centimeter (ions/cm3) in pristine natural environments. At sea level ion density is typically around 500 negative and 600 positive ions/cm3. In cities and inside buildings ion levels drop by 80% to 95% and can be barely detectable in small spaces.

As ion density decreases, so does the air quality. By increasing the quantity of both positively and negatively charged small oxygen ions, air quality is improved.

How Bi-Polar Ionization works

Much like sunlight does in the atmosphere, BiPolar ionization technology produces a natural bio-climate rich in positive and negative oxygen ions.

The negative ions contain an extra electron while the positive ions are missing an electron resulting in an unstable condition.

In an effort to re-stabilize, these bipolar ions seek out atoms and molecules in the air to trade electrons with, effectively neutralizing particulate matter, bacteria and virus cells, odorous gases and aerosols, and VOCs.

© Photo Credit: Plasma-Air

How Au Pure can assist

At Au Pure, we integrate Air Quality Solutions to provide contamination control along with other solutions.

Au Pure is an Air Quality Solutions Integrator for indoor spaces be it:

· Contamination Control in high-occupancy or critical areas

· Odor management

· Smoke filtration / control

· Energy Management (in HVAC / Air Quality solutions)

· Overall Air Quality solutions

Au Pure partners with world’s leading UVC systems manufacturer, Steril-Aire and also the world’s leading Bipolar Ionization systems manufacture, Plasma-Air to bring integrated technology solutions either are direct fitment or as integrated solutions along with our technical expertise and support for solution design, project management and lifecycle maintenance of the solution.

With a multi-sector experience and dedicated solution sets for each sector, here are some of the reasons why Au Pure is client’s partner of choice for all Air Quality & Energy Management needs:

Air Treatment and Contamination Control

• Integrated Air Treatment Solutions

• Ionization (Both Negative Ionization & Bi-polar Ionization)

• UVC / UVC + Oxidation

• Oxidation / Ozone

• Particulate removal

• Bespoke/Specialized Filtration for Microbial Control

 

Integrated Smoke Filtration Solutions

• Multi-stage / Multi-technology Smoke Filtration

• Odor Management Systems

• Concealed Units / Cassette Type / Wall Mount

Odor Management

• Integrated Odor Systems

• Waste Odor Treatment System

• Aroma Diffusion

Energy Management

• Sensor Controlled Demand Operated VFD Efficiency

• IAQ Based HVAC Design Systems

Bespoke Solutions

• Based On Specific Project Requirements

For more information, you can visit us at www.au-pure.com or contact us at IAQ@au-pure.com

Bibliography:

[1] J. P. Duguid, M.B., B.Sc., “The Size and the Duration of Air-carriage of Respiratory Droplets and Droplet-Nuceli\

[2] S. C. Antopol and P. D. Ellner, “Susceptibility Of Legionella Pneumophila To Ultraviolet Radiation,” Appl Environ Microbiol, vol. 38, pp. 347-8, Aug 1979.

[3] J. A. Bernstein, et al., “Health Effects Of Ultraviolet Irradiation In Asthmatic Children’s Homes,” Journal of Asthma, vol. 43, pp. 255-262, 2006.

[4] H. Schleibinger, “Growth Of Microorganisms And Production Of MVOC On Air Filters Of HVAC Systems In Two Different Polluted Areas,” presented at the

Indoor Air 99/Conference of IAIAS, Edinburgh, Scotland, 1999.

[5] R. Nagy, “Application of Ozone from Sterilamp in Control of Mold, Bacteria, and Odors “ The American Chemical Society, 1959.

[6] E. L. Galson and J. Guisbon, “Hospital Sepsis Control and TB Transmission,” ASHRAE Journal, vol. May, pp. 433-438, 1995.

[7] F. Blosser. “Simulates Hospital Room to Test UV System for Employee TB Protection,” NIOSH-Funded Study, 2003. Available: http://e-co.uk.com/uvgi/nioshtb.pdf

[8] D. H. Mahoney, et al., “An Outbreak Of Aspergillosis In Children With Acute Leukemia,” Journal of Pediatrics vol. 95, pp. 70-72, 1979.

[9] A. S. Breathnach, et al., “An Outbreak Of Multi-Drug-Resistant Tuberculosis In A London Teaching Hospital,” J Hosp Infect, vol. 39, pp. 111-7, Jun 1998.

[10] A. Hollaender, “Effect Of Long Ultraviolet And Short Visible Radiation (3500 To 4900A) On Escherichia Coli,” J Bacteriol, vol. 46, pp. 531-41, Dec 1943.

[11] G. Shama, “Inactivation Of Escherichia Coli By Ultraviolet Light And Hydrogen Peroxide In A Thin Film Contactor,” Letters in Applied Microbiology, vol. 15, 1992.

[12] K. Oguma, et al., “Photoreactivation Of Escherichia Coli After Low- Or Medium-Pressure UV Disinfection Determined By An Endonuclease Sensitive Site

Assay,” Appl Environ Microbiol, vol. 68, pp. 6029-35, Dec 2002.

© Au Pure