Is an Air Purifier Good for Asthma?

Asthma Air Purifier

According to Asthma Canada, asthma is the third most common chronic disease in the country, affecting more than 3.8 million Canadians. Although there is currently no cure for asthma, steps can be taken to effectively control the symptoms and prevent severe outcomes.

Find out more about asthma and whether air purifiers can be used to give those living with the condition a better quality of life!

What is asthma?

People with asthma have particularly sensitive airways that tend to overreact when irritated. Muscle spasms, inflammation and mucus cause the airways to narrow, making it difficult to breathe. Common symptoms include shortness of breath, chest tightness, wheezing and coughing.

Asthma ranges in severity from mild, occasional symptoms to serious attacks that can lead to hospitalization and even death.

Asthma triggers

Asthma triggers are things that irritate the sensitive airways of asthmatics, causing attacks and/or making symptoms worse. Triggers differ from person to person, and an individual can have more than one.

Asthma often occurs in conjunction with allergies. People with both usually find that environmental allergens will trigger their asthma symptoms. Common allergic triggers include pet dander, dust mites, mold and pollen.

Other types of irritants include cigarette smoke, dust, air pollution, strong smells, viral infections and exercise. If you have asthma, it’s important to know what your triggers are so that you can take steps to avoid and/or mitigate them.

How air purifiers can help with asthma

Air purifiers are designed to eliminate the fine particles present in indoor air. Many are equipped with HEPA filters that are adept at capturing even the trickiest sizes of particles. Air purifiers with HEPA filters can effectively trap many of the most common asthma triggers, including dust, dander and pollen, cleaning the air and helping to mitigate asthma symptoms. There are also whole house air purification systems with UV technology that are designed to deactivate and destroy airborne microorganisms such as dust mites, mold spores and viruses.

There’s no question that air purifiers improve indoor air quality and safety, and reducing the prevalence of asthma triggers is an important step in managing the condition. That being said, it’s a good idea for people with asthma to use other mitigation methods in conjunction with air purifiers for best results.

Breathe easy with Sanuvox!

For people with asthma, avoiding triggers and managing symptoms can be a daily challenge. Fortunately, modern technology provides a variety of solutions that can contribute to a comprehensive mitigation strategy!

Sanuvox is a global leader in UVC air purifiers. Our residential UV air purifiers are equipped with proprietary UV technology that effectively destroys contaminants and degrades chemicals and odours for cleaner, purer air. Invest in your health and well-being—contact us today!

Is Hospital Air Clean?: Hospital Air Quality 101

Hospital Air Quality

We tend to think of hospitals as places of healing, not places where we risk catching infectious diseases. However, during the worst waves of the pandemic, droves of people avoided emergency rooms for fear of catching the virus. And the truth is that patients in hospital settings have been threatened by infectious diseases long before the advent of COVID-19.

How dangerous is it to simply breathe the air in hospitals? What can be done to eradicate the airborne pathogens that circulate in hospital settings, threatening the lives of patients? Find out in this article!

The potential for infection in hospitals

People can become infected with bacteria, viruses, fungi and other microorganisms through airborne transmission and contact with infected people or contaminated surfaces, fluids or food. When these infections occur in hospital settings, they are called nosocomial infections. Health care-employees need to clean and purify the surrounding of patients to prevent hospital acquired infections.

In Canada, more than 65,000 patients have contracted infections of COVID-19 while receiving health care treatment. This number has had a significant impact in health care services, due in part to the emergence of pathogens that are more and more resistant to antibiotics and need more medical attention from health care workers.

Without diligent infection control measures, the pathogens circulating in hospitals pose significant risks to patients. We see it every year with the increase of C. Difficile or other strong bacteria.

Infection control strategies

There are a variety of strategies that can be used to control the rate of infection in healthcare settings, some focusing on contact with people and surfaces, others focusing on mitigating airborne transmission.

Hand hygiene

Hand hygiene is vitally important for both healthcare workers and visitors. Improving hand hygiene by just 20% reduces the rate of infections. Hands should be washed frequently with soap and warm water for at least 20 seconds. Alcohol-based hand sanitizer can also be used.

Surface disinfection

Many infections can be transmitted through contact with contaminated surfaces. It’s important for medical equipment and surfaces to be disinfected shortly after each time they are used in order to prevent transmission. In addition to traditional cleaning methods, UV technology such as Sanuvox products, can be used for surface disinfection.

Environmental infection control

There are four types of environmental infection control that can be implemented in hospitals to mitigate airborne transmission.

  • Dilution consists of introducing fresh air from outside to dilute the contaminated air. Unfortunately, it is often impractical to continually replace all contaminated air with outdoor air due to the expense of conditioning it, so while this practice can be helpful, it is not enough on its own. In addition, the operating costs surrounding the number of air changes per hour must be considered. In use, these costs can become exorbitant, especially during periods of extreme cold.
  • Filtration consists of installing air filters to trap microorganisms. Although air filtration has been widely adopted by medical facilities, studies have shown that it is inadequate when it comes to controlling airborne pathogens. Air filters have trouble trapping certain sizes of particulates, meaning that many microbes are still able to pass through.
  • Pressurization consists of using air pressure to create self-contained spaces in order to protect against cross-contamination from one space to the next. Unfortunately, this method is difficult to control. Disruptions as simple as frequently opened doors can considerably lessen its effectiveness.
  • Disinfection consists of using equipment that neutralizes the pathogens in the air. Medical-grade air purifiers with UV technology are ideally suited for this purpose.

The advantages of UV-C technology as a disinfection strategy

UV technology uses a particular wavelength of ultraviolet light to deactivate and destroy microorganisms of all kinds, rendering them harmless. Science has not yet found any microorganism that can resist the destructive effects of the 254-nm germicidal wavelength emitted by UV-C lamps.

UV-C is a tried-and-true disinfection method that has been used for medical equipment and air sterilization in hospital settings for over 70 years. However, since the 1950s, the medical system has become increasingly dependent on antibiotics and has consequently under-utilized preventive UV-C technology. Now, with the advent of antibiotic-resistant “superbugs”, healthcare facilities would be well-advised to make use of UV-C disinfection .

There are two applications for UV-C technology against airborne infectious agents: in-room units and in-duct HVAC systems. In-room disinfection units interrupt airborne transmission in patient rooms, waiting rooms, hallways, stairwells, etc. They use a fan and an intense concealed UVC source to intercept and deactivate the pathogens at the source, as they are being generated by humans. HVAC in-duct UV-C disinfection prevents microbes from proliferating and spreading in the HVAC system, which would otherwise provide an ideal conduit for them.

Breathe clean air with Sanuvox

Unless it is properly sterilized, hospital air is not clean. In fact, it can contain a variety of pathogens that can cause infection and threaten patients’ lives. It is vitally important for health care facilities to use the proper environmental infection control methods to clean the air and lower the risk of airborne transmission.

Sanuvox is the North American leader in medical UV disinfection systems. Our high-efficiency UV air purifiers deactivate and destroy airborne pathogens, and our UV surface disinfection units efficiently sterilize rooms and medical equipment. Shop our store today for first-rate disinfection solutions that will reduce the incidence and improve the health and safety of everyone at your facility.

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.







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El Periódico reports on a new method of disinfection (article in Spanish)

El Periódico reports on a new method of disinfection (article in Spanish)

Utilizando la combinación de la luz UV, la nebulización o microdifusión molecular, la pulverización y la aplicación directa para la eliminación del SARS-Cov-2.


Equipos UV EULEN Limpieza Hospitalaria. / EPDA

EULEN Limpieza, actividad del Grupo EULEN, líder en nuestro país en el diseño de servicios a empresas y siguiendo con su objetivo de ofrecer a la sociedad servicios innovadores que aportan soluciones útiles, de calidad y sostenibles, ha concluido -tras multitud de ensayos realizados por su departamento Técnico de higienistas exclusivo para el entorno Hospitalario y de un equipo de I+D+I- que la mejor técnica para eliminar virus, bacterias, hongos y agentes contaminantes orgánicos similares en entornos sanitarios es una combinación de diferentes técnicas aisladas.

La efectividad que cada una de ellas tiene en diferentes aspectos, hace que dicha combinación de técnicas específicas como laluz UV, la nebulización o microdifusión molecular, la pulverización y la aplicación directa sea la técnica definitiva en la limpieza hospitalaria frente al SARS-Cov-2.

Tecnología puntera

Actualmente la compañía dispone de los equipos más avanzados a nivel mundial y que otorgan una máxima seguridad de utilización tanto para los operarios que los manejan como para cualquier usuario del espacio tratado, especialmente en el ámbito hospitalario.

Destacan las unidades del equipo Asept.2x de Sanuvox Technologies, empresa canadiense líder de su sector. Este dispositivo puntero en desinfección por luz ultravioleta se utiliza tanto en quirófanos como en habitaciones. La luz UVC y la luz UVV del equipo tienen la misma longitud de onda que la producida por el Sol y ataca a los microorganismos a nivel molecular, desactivando y destruyendo los contaminantes, así como degradando los agentes químicos y olores. A diferencia de las lámparas convencionales, los sistemas de purificación UV que utiliza EULEN Limpieza usan un proceso patentado diseñado para entregar la máxima cantidad de luz UV.

Para complementar el sistema de desinfección por UV, la compañía emplea la última tecnología en nebulización y pulverización de generación de niebla nano y micrométricacon dinámica inductiva. Es la misma tecnología que en la actualidad está siendo usado también por las Unidades Tecnológicas de Cuerpos de Seguridad del Estado en la lucha contra el Sars-COV-2. Dotado con la última tecnología de desinfección mediante chorro regulable que permite desinfectar las estancias en un corto tiempo, minimiza tanto el desinfectante utilizado como los residuos y posibles daños a personas e infraestructuras. Asimismo, permite tratar grandes áreas en cortos periodos de tiempo, accediendo a todas las superficies y zonas de difícil acceso, realizando el perfecto mojado de todas las superficies a desinfectar.

Por último, de acuerdo a su política de utilización de los mejores biocidas del mercado, desarrollados por las empresas líderes, junto a los profesionales formados y acreditados acorde con la normativa establecida por el Ministerio de Sanidad en cuanto a la aplicación de Biocidas,se selecciona en cada momento el más conveniente para aplicar por el método óptimo en función de las necesidades. Por ello, es importante distinguir entre los de un espectro más específico de los de amplio espectro.

En definitiva, la combinación de todas estas técnicas y tecnología se convierten en la mejor solución frente a la COVID-19 en espacios hospitalarios y aseguran un resultado óptimo en desinfección en el menor tiempo posible.

En la actualidad, numerosos hospitales de la Generalitat Valenciana y otros de referencia en la geografía española confían en las soluciones de EULEN Limpieza cuya estructura y forma de trabajo propia asegura el mejor resultado en un entorno como el sanitario.

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El Mundo reports on ASEPT.2X in Spain (article in Spanish)

El Mundo reports on ASEPT.2X in Spain (article in Spanish)

Para Héctor Atienza

La Clínica Universidad de Navarra emplea un máquina pionera en España que desinfecta de COVID-19 las habitaciones del hospital en poco más de cinco minutos con rayos UV. Estos modelos se fabrican en Canadá y cada equipo cuesta hasta 160.000 euros.

Dos máquinas UVR desinfectando un quirófano en la Clínica Universidad de Navarra.

La lucha contra el Covid-19 también se pelea estos días al milímetro en cada rincón de los centros hospitalarios por los equipos de limpieza. El coronavirus ha demostrado tener una alta capacidad de transmisión y fácil apego a todo tipo de materiales de forma invisible. Su resistencia complica las labores de desinfección de las salas en plena crisis sanitaria.

Una de las técnicas más innovadoras en esta particular batalla contra el virus son las lámparas germicidas de irradiación ultravioleta (UVGI). Con esta tecnología tanto las estancias de los hospitales como los quirófanos quedan libres del bicho tras su paso en un corto periodo de tiempo.

“Son muy efectivas porque destruyen tanto el ADN como el ARN, donde está la programación genética de los virus y las bacterias. Una destrucción total en poco tiempo que permite el acceso casi inmediato a las estancias”, destaca el doctor de la Clínica Universidad de Navarra, Francisco Guillén Grima, cuyos centros en Madrid y Pamplona aplican esta técnica pionera de trabajo.

Se trata de una tecnología relativamente novedosa en España. Con las técnicas tradicionales de esterilización de espacios, como el peróxedo de hidrógeno y las botellas de gas o vapor, los pacientes deben esperar entre una y tres horas para poder acceder a la habitación. Mientras que los equipos ASEPT-2x UV permiten su entrada en poco más de 10 minutos después de la salida del último paciente.

El médico Guillén Grima posando junto a un modelo ASEPT-2X UV.

“Las recibimos hace justo ahora dos años. La primera vez que las utilizamos fue porque se había intervenido quirúrjicamente a un paciente infeccioso, pero el quirófano se necesitaba urgente para un transplante cardiaco. En estos casos, te avisan cuando hay una posible donación y se debe actuar de inmediato. Metimos las dos torres y en 20 minutos el quirófano estaba operativo“, añade Guillén Grima que también fue uno de los 70 científicos que firmaron el manifiesto enviado en marzo a Pedro Sánchez solcitando el confinamiento de la población.

Fabricados por la firma canandiense Sanuvox, los equipos tienen una altura de 1,60 metros y poco más de 71 centímetros de ancho. Con apenas 45 kilos de peso, su transporte se realiza de forma sencilla con sus ruedas guía por todas las dependencias del hospital.

El único inconveniente que pueden tener estos equipos son las zonas de sombra que genera la lámpara UV cuando actúa. Para contrarrestar este hándicap, el personal técnico sitúa la máquina en varios puntos de las habitaciones evitando así cualquier recoveco con virus.

“Uno de los equipos se compone de dos torres que trabajan simultáneamente y cada lámpara se activa cinco minutos. Pero ahora con el tema de coronavirus hemos subido a seis minutos para asegurar la desinfección como un margen de seguridad total. Con la crisis del coronavirus también hemos alquilado cuatro torres más porque no dábamos a basto“, añade el especialista.

Son equipos caros. Según ha podido confirmar EL MUNDO, cuestan entre 60.000 y 140.000 euros, en función de las características del modelo. Algunos fabricantes ya ofrecen versiones que se mueven de forma autónoma por las instalaciones hospitalarias. Sin embargo, la clave del equipo está en el software que registra la máquina vía Wifi en el servidor del hospital. Pueden ofrecer diferentes soluciones tanto de servicios como de control de salud.

“Al quemar el polvo, también se produce cierto olor que se va enseguida. Si quieres que no huela a ozono, hay modelos que llevan unos filtros, pero la máquina cuesta más cara”, destaca el doctor Guillén Grima.

Estos equipos, que en España son distribuidos por la empresa tecnológica Alfatec Sistemas, también están presentes en los centros de la Fundación Jiménez Díaz en Madrid, del grupo QuirónSalud, y en la empresa de servicios generales Eulen.


La técnica de desinfección ultravioleta, con una lámpara de pequeñas dimensiones, también se utiliza en los hospitales para limpiar de gérmenes en equipos de uso habitual entre pacientes y en parte del material médico. Sin embargo, este equipo también hace una especial labor desesterilizando los mandos a distancia de las televisiones.

“Es un equipo que se toca mucho por pacientes y acompañantes. Nosotros ahora los metemos en la máquina y salen dentro de una bolsa precintada. También los usamos con los termómetros, endoscopios… Es una técnica nueva que tendrá mucho futuro en España”, añade el médico.

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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

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Collingwood Hospital first in Canada to have self-sanitizing Patient Rooms

BradfordToday reports on Collingwood hospital first in Canada to have self-sanitizing patient rooms

By Erika Engel

UV light, ozonated water, copper-infused surfaces, and titanium dioxide have all come together to make Canada’s first self-sanitizing patient room and bathroom at Collingwood General and Marine Hospital.

There’s copper in them there walls.

Collingwood General and Marine Hospital (CGMH) has opened the first of five self-sanitizing rooms, and will be the first hospital in Canada to use copper-infused panels on the walls in its hallways and patient rooms to prevent bacteria growth. 

Copper is naturally anti-bacterial and copper surfaces prevent bacteria growth.

The made-over patient room is located on the medical floor, and it’s packed with the latest technology in sanitization from the UV lights on the ceiling to the copper-infused toilet seat in the bathroom.

Norah Holder, CGMH president and CEO, said Collingwood’s hospital is the first in Canada to combine all of the self-sanitizing elements into one patient room and bathroom.

The bacteria-fighting technology includes copper-infused high touch surfaces like the bed rail, the door handles and pulls, the toilet seat, and the toilet handle. There’s UV lights on the ceiling that run on a disinfecting cycle when the patient is in the bathroom or outside the room, and there are plastic panels on the bottom half of the wall coated in titanium dioxide, which reacts with UV light to kill bacteria. In the bathroom a no-touch sink is engineered to prevent splashing and delivers ozonated water. Ozone has been proven to have an oxidizing, antiseptic, and germicidal effect. More UV lights in the bathroom activate after every use, bathing the room in UV light, which destroys the cell wall of bacteria, spores, and fungus.

The next rooms completed will have copper-infused panels covering the bottom half of the walls.

According to John Widdis, manager of operations and maintenance at CGMH, Collingwood will be the first hospital to use these panels as they are new to the market.

He said the technology doesn’t take away the need for cleaning, rather it mitigates the bacteria load on surfaces in the room. Rooms will still be cleaned once every 24-hours at minimum.

Swab tests showed bacteria counts in the range of 7,000 to 8,000 in a typical room. After the self-sanitizing technology was installed, the same swab tests are showing bacteria counts in the range of 30-50.

Dr. Michael Lisi, chief of staff at CGMH, said he’s “thrilled” to see CGMH become a leader in infection control technology locally, provincially, and nationally.

“This technology is really going to provide benefits in terms of patient safety, and safety of staff and visitors,” said Lisi. “I can have faith in such technology to provide the best level of care for our patients. This will help with improving outcomes and getting patients back to their families safely.”

CGMH has been testing some of the technology in its emergency department already. Widdis said he wanted to start with the one public washroom in the department once he watched the constant flow of people using the facility. The bathroom was cleaned once every 1.5 hours, but in between there would be eight or so people using it.

When the emergency department was renovated in 2016, Widdis had an ozone sink and some other self-sanitizing technology installed in the bathroom. Staff sinks were also replaced with models that delivered ozone water.

Since then, the hospital has seen the lowest rates of C-Difficile occurrences in recent history.

Lisi said the rates are the lowest they’ve been in six years. Widdis said the rates went down almost as soon as the changes were made in the emergency department.

“[Infection control] is a very significant component,” said Lisi. “It’s something all hospitals struggle with … C-Difficile can be life ending in elderly and those whose immune systems are not strong enough.”

Widdis has been at CGMH for 29 years and he’s seen hospitals and researchers work to battle hospital acquired infection rates over the course of his career.

In the beginning, said Widdis, it was done with chemicals, later it was bleach and hydrogen peroxide on surfaces. Before the UV lights, copper infused materials, and ozone water sinks, the last innovation was a “bomb” that would vaporize hydrogen peroxide to sanitize surfaces.

“We still use some of them,” said Widdis, adding the chemicals have moved to more earth-friendly compounds. “These are just more weapons we use in our fight against hospital acquired infections.”

The technology now installed on the medical floor will also continue to work against mutating strains of bacteria.

Widdis said staff decided to start installing the technology on the medical floor because it’s where patients would be isolated in cases of infection.

“If we have an outbreak, which we haven’t in years, this is the floor where we run into the most trouble,” said Widdis.

Work is continuing to outfit four more patient rooms and renovate hallways to include fresh paint and copper-infused panels on the walls. There are also plans in the works to outfit all hospital bathrooms with copper-infused toilet seats, high touch areas, ozone sinks and UV light.

For rooms not equipped with UV lights yet, the hospital has two portable towers with UV lights that can be used to disinfect any room.

Holder is looking forward to using this and even newer self-sanitizing technology in the future hospital build.

The CGMH foundation raised $1 million for the project through the Tree of Life campaign held at Christmas and other initiatives.

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UV Disinfection: A Comparative Technology Review of Continuous UVC & Pulsed Xenon UV

Infection Prevention: Environmental Cleaning and Practical Infection Control

By Barry Hunt, Class 1 Inc., Canada

Recent events in the US healthcare industry have combined to create a rush by healthcare facilities toward the adoption of technology for total room disinfection. Events include: 1) changes to the Affordable Care Act that reduced CMS and insurer compensation to hospitals due to high rates of Healthcare Acquired Infections (HAIs); 2) elimination of CMS and insurer reimbursements to hospitals for individual patient healthcare costs if and when a patient develops an HAI; 3) a number of peer-reviewed publications of total room disinfection systems used at terminal discharge demonstrating successful reductions of either bioburden or HAIs or both; 4) presenter advocacy at recent infection prevention professional conferences including American Prevention and Infection Control (APIC) and Society of Healthcare Epidemiology of America (SHEA); 5) industry innovation; and 6) industry promotion.

In the ensuing market competition between hydrogen peroxide vapor (HPV) fogging and UV total room disinfection systems, UV appears to be the leader in the U.S., likely for reasons of speed, safety and ease of use19. Well-trained housekeeping staff can completely disinfect 20 to 50 patient rooms per day depending on the speed of the mobile UV system chosen. The faster the disinfection system, the faster the room turnaround, and the greater the improvement in hospital revenue; the less EVS staff time required, the lower the hospital operational costs; and there is no risk to staff or patients of exposure to residual aerosol disinfectant.

Of the two types of energy-based disinfection systems being marketed today, UVC has been a proven technology for disinfecting air, water and instruments for over a century2,3. UVC is a narrow spectrum technology operating at a frequency of 254 nm, very close to the optimal germicidal frequency (263 nm to 266 nm) for bacterial and viral disinfection.

PX light is a broad-spectrum technology developed in the 1950s primarily for flash photography. PX does however include some germicidal UV in its range of emitted light frequencies.


Narrow spectrum UVC emitters are relatively efficient at generating germicidal UV with a known range of efficiency from 24% to 38%. That means a bulb rated for 100 W input power from one manufacturer may emit 24 W of germicidal UV, while a 100 W bulb from another device manufacturer may produce as much as 38 W of germicidal radiation. Technologies known to impact this range include tubing materials, and temperature management. Further optimization of emission of UV energy onto surfaces can be accomplished with reflectance technology.

By contrast, PX bulbs are relatively inefficient at generating germicidal UV with a published efficiency of just 9%. Much of the input energy is wasted as heat and visible light, rather than being converted to germicidal UV. Consequently, for any given input power, a UVC lamp will emit approximately 4 times more germicidal UV than its PX counterpart.

Given the example of a typical US hospital receptacle that supplies up to 2000 watts of electrical power, the maximum germicidal UV output of a PX device can only be 180 Watts (9 % x 2000 watts = 180 watts), whereas a UVC device can generate 760 Watt of germicidal UV (38% x 2000 watts = 760 watts).

Disinfection efficiency is a direct function of the delivered germicidal UV power and exposure time. Therefore, it becomes quite clear that UVC can disinfect up to 4 times faster, or 4 times more, than a PX device from a single emitter using the same power (760 watts / 180 watts = 4.2X).


UVC constants have been published for all bacteria and viruses allowing easy calculation of time and power required for deactivation with germicidal UV. Disinfection constants vary greatly with the organism. In general, vegetative bacteria are deactivated very quickly, spores require a lot more time.


At a UVC energy dose of 400 mJ/cm2, all known epidemiologically important pathogens (EIP), including Clostridium difficile spores, are rendered inert. Germicidal UV creates thymine-thymine dimers and thymine-cytosine dimers of neighboring molecules on strands of DNA and RNA, preventing organism replication.

The higher the emitted energy of the device, the faster the target energy dose is reached, and the faster the disinfection cycle. For example, if the device emitted 400 mJ/cm2/minute at the target distance, only one minute of operation would be required for disinfection. If the device emitted 40 mJ/cm2/minute (more commonly expressed as 0.667 mJ/cm2/s i.e. 0.667 mW/cm2) at the target distance, then 10 minutes would be required to achieve the same disinfection dose.


Life Cycle / Maintenance:

The life of a PX bulb is counted by the number of pulses it can sustain before the electrodes are destroyed. Typical published values for PX life-cycle range from 1 to 10 million pulses. Assuming an average life cycle of 5 million pulses, and a flash rate of 3 times per second, (the value reported by one PX manufacturer), this will only result in an expected life of 463 hours. (5 million / 3 = 1.67 million seconds = 463 hrs.) Given that a typical disinfection cycle lasts 15 minutes according to one PX manufacturer, this means that the PX lamp will need to be replaced after 1,852 cycles. Assuming the PX unit is used 20 times per day, then the PX lamps will need to be replaced every 3 months.

By comparison, the published life expectancy of a typical UVC lamp is between 10,000 and 17,000 hours. For at least one manufacturer, that could mean bulb replacement as little as every 5 years.

Operational & Proximity Safety:

Because of their inherent high temperature flash operating mode, PX lamp surfaces become extremely hot (1000 oC) and may become a fire hazard or cause severe injuries if accidentally touched after discharge (similar to a burnt flash bulb from a 1950s flash camera). In addition, the gas pressure that builds up inside the hot lamp becomes pressurized to several atmospheres and can explode violently projecting glass debris. This may be the reason at least one PX manufacturer retracts the PX lamps into a protective canister immediately after discharge.

Viewing Safety:

UVC can be safely and comfortably viewed from behind glass. UVC does not penetrate glass or plastics. This allows high visibility of the disinfection process in glass-walled areas like ICU.

Conversely, PX devices discharge an intensely bright fast-paced strobe of visible light. Staff need to be trained to protect patients, visitors and staff from accidentally viewing the device through glass while in operation. This may require installation of additional curtains or blinds, as well as training of EVS staff and clinical staff working in commonly glassed areas such as ICU. Even casual contact walking beside partially covered glass can subject passersby to discomfort from the intense white light flash.


At least one PX manufacturer promotes the fact their product does not contain mercury. True. Conversely, UVC lamps do contain a tiny amount of mercury, the same as every fluorescent lamp used throughout hospitals, commercial and industrial buildings and residences all over the world. The amount of gaseous mercury that could be released from a broken UVC lamp in a hospital is much too low to create a health risk. Many manufacturers also encapsulate their lamps in a protective Teflon sleeve that both eliminates any possible release of mercury vapor and serves to protect occupants from exposure to fragments of broken glass in the event of breakage.



All light energy, whether visible or invisible, UV or non-UV, UVC or PX, follows an inverse square law. If the distance from the point source to the target doubles, the energy decreases to 25%. Conversely, if the distance to target is halved, the energy density quadruples. Thus whether using 9% efficient PX or 38% efficient UVC, using two emitters instead of one would cut the distance to target for all surfaces in half and would reduce the room disinfection time by 75%.

A further effectiveness optimization strategy would be to locate the two emitters equidistant on either side of the patient bed with an overlap pattern of UV emission and set to achieve a Log6 reduction on the most distant outer wall surface. This would double the germicidal UV in the vicinity of the patient bed between the emitters, the most critical area in the room, and provide up to a Log12 reduction. Adding additional emitters would shorten room disinfection time even further but the law of diminishing returns would suggest two to three emitters is optimum.


Both UVC and PX have been shown to dramatically reduce bioburden and HAIs. However, UVC appears to be 4 times more energy efficient than PX, and 4 times faster or more effective than PX. UVC appears to provide 10 times longer lamp life and dramatically lower life cycle costs than PX. UVC does not expose staff to the risk of contact with excessively high temperature, or exploded lamps that PX may. UVC can be safely and comfortably viewed while in operation from behind glass or plastic whereas PX presents a risk of temporary blinding or discomfort for passersby.

All germicidal UV systems can substantially shorten room disinfection times and optimize room turnaround using two or three emitters.

UVC appears to offer significant technological, operational, safety and cost advantages over PX. Perhaps that is why UVC is the predominant air, water and surface disinfection technology used in all other industries. There are millions of UVC installations worldwide and no apparent movement afoot in any industry to switch from UVC to PX. The market share for UVC in other industries is likely in the order of 99.99%. Perhaps we should pause to consider that context, as well as the safety, operation, efficiency, efficacy, life-cycle and maintenance costs, when we consider our options for germicidal UV surface disinfection for healthcare.


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New Sanuvox Mobile UV Sterilization System for Hospitals

New Sanuvox Mobile UV Sterilization System for hospitals

Sanuvox releases the ASEPT.2X mobile UV sterilization system to help reduce nosocomial infections in hospital environments.

The ASEPT.2X mobile UV sterilization system uses a primary and secondary unit to sterilize high-touch surfaces with ultraviolet ‘C’ energy controlling (6 log reduction) drug-resistant microorganisms, such as MRSA and C. diff. in less than 10 minutes in a standard patient hospital room. The two-unit operation dramatically lowers the sterilization time typically associated with UV sterilization, while achieving exceptional deactivation rates by minimizing shadow areas through the use of the two-unit system.

Studies show that even with the best terminal cleaning practices, an operating or patient room can remain the source of many potential harmful drug-resistant microorganisms as manual cleaning effectively cleans less than 50% of surfaces. In the US it is estimated that HAIs (Hospital Acquired Infections) result in 1.7 million infections and 99,000 deaths costing the healthcare system between 28 to 33 billion dollars annually. Statistics show that one in every 20 patients admitted to a US hospital falls victim to an infection they contracted while there.

UV sterilization (UVC 254nm wavelength) has been used in hospitals for decades. Commercially available mobile UV systems are used to sterilize the patient room in the terminal cleaning process. However, the limitation to UV sterilization is that it is a “line-of-sight” technology. UV sterilization is ineffective in shadowed areas where the light cannot reach. This can include the other side of high-touched areas, such as a remote or call button or the other side of a bed or bed rail. As such, conventional UV systems require multiple positioning within a room to lessen the chances of shadow areas that block the sterilizing ability of the UV light. In doing so, time and resources are spent moving the system around the room and preparing the room for additional treatments.

The ASEPT.2X mobile UV sterilization system has been tested by ATS Labs in Minnesota (USA) to show a 99.9999% reduction in MRSA and C. diff. in less than 5 minutes around high-touched areas close to the patient bed, and under 10 minutes throughout the rest of the room. The ASEPT.2X is also being evaluated in one of the nation’s leading teaching hospitals.

The now readily available ASEPT.2X includes many firsts incorporated into a mobile system. Some features include a total of eight infrared motion detectors (360 degree protection around each of the two units) that will shut the units down should any personnel enter the room during the sterilization process. Wi-Fi communication between both primary and secondary units controlled and monitored by any smart device while logging all sterilization cycles.

According to Normand Brais, Ph.D., Founder and VP Engineering at Sanuvox, “The ASEPT.2X UV system helps eliminate the one limitation in UV sterilization, shadows. By maintaining a closer proximity to high-touched areas and reducing shadow areas by treating both sides of the patient bed and surrounding areas, Sanuvox is able to deliver an elegant solution in reducing HAIs while increasing productivity.” The idea is to make the ASEPT.2X easily accessible to virtually any medical facility looking to implement the system.

Although single UV systems can sell for well over US$100,000, Sauvox believes that with every unit in operation, it can save lives and wanted the systems priced right to do so. As such, a fully equipped two-unit ASEPT.2X system will sell for considerably less, making the unit readily available to most who are looking into the technology.”

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