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Far-UVC light

The promising possibilities of 222nm

The disinfection technology we need right now

We need technology that inactivates harmful pathogens and helps people feel safe in indoor spaces—effective disinfection technology that adds a layer of defense as part of a multi-disinfection strategy like regular cleaning.

Urbanization, worldwide population growth, and global travel contribute to diverse contact among people, livestock, and wildlife, increasing the frequency and transmission of new pathogens that may harm us. We need safe and effective disinfection technology that reduces pathogens now, and for the future.

222nm: A sweet spot on the UV spectrum

Conventional germicidal lamps emit UVC light with longer wavelengths (>230nm) that also effectively reduces airborne and surface pathogens but present a human health hazard. What’s new is the discovery and application of far-UVC 222nm light, a sweet spot on the UV spectrum, to effectively inactivate pathogens with people present.

Recent research shows that far-UVC 222nm light—paired with an optical filter that prevents longer (>230nm) harmful wavelengths from being emitted—can reduce more than 99% of pathogens like SARS-CoV-2 (COVID-19) and influenza, as well as antibiotic-resistant bacteria like MRSA and E. coli, and allows for constant pathogen-reduction because it’s safer for use around people.

Read the far-UVC 222nm white paper

Read the Far-UVC 222NM white paper

What’s the difference between 254nm and 222nm far-UVC light?

This graphic illustrates why 254nm (and longer) wavelengths present a human health hazard to unprotected eyes and skin.

This graphic illustrates a significant difference between 254nm and 222nm light: the shorter wavelengths of far-UVC 222nm light are unable to penetrate past the protective outer layers of our skin and eyes.

This graphic illustrates how far-UVC 222nm light inactivates airborne and surface pathogens like SARS-CoV-2 (COVID-19) by damaging its RNA. Not shown: The same light neutralizes bacteria by damaging its DNA.

Christie CounterAct with Care222: A world-first

Christie CounterAct commercial UV disinfection fixtures contain patented Care222® technology that emits filtered far-UVC 222nm light, designed to neutralize pathogens with people present while meeting established safety guidelines. Care222 is also the world’s first UVC technology with a proprietary optical filter that blocks potentially harmful UVC wavelengths from being emitted.

Care222 is the world’s first far-UVC technology that may be used around people and is effective in reducing pathogens, and the only that contains a proprietary filter to prevent longer UVC wavelengths from being emitted.

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Patented Care222 technology

Care222 excimer lamps produce far-UVC 222nm light

Here’s how: Care222 Krypton-Chloride (KrCL) excimer lamp modules contain a chamber filled with noble gas that doesn’t use inner electrodes and is completely mercury-free. High voltage applied across the outside of the glass excites the gas inside, causing far-UVC 222nm light to be emitted. And the construction of Care222 lamps allow them to instantly turn on or off without warm-up time or decreased lifetime, unlike other similar lamps.

The world’s first far-UVC technology with a proprietary optical filter

Care222’s proprietary optical filter prevents longer UVC wavelengths (>230nm) that present a human health hazard from being emitted—an especially important feature that other 222nm and far-UVC-emitting products do not have.

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Far-UVC 222nm: The disinfection technology we need now and for the future


Technology backed by research: What the studies say

Columbia University Irving Medical Center – February 2017

A Columbia University Irving Medical Center study published in February 2017 found that far-UVC 222nm light is as effective at killing (antibiotic-resistant) bacteria as conventional germicidal UV lamps that use 254nm light, but without any associated skin damage risks.

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Kobe University – May 2020

A Kobe University study published in May 2020 found that far-UVC lamps can be used as an alternative to 254nm, since 222nm exerts a comparable disinfection ability but can be safely used for sterilizing human skin.

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Columbia University Irving Medical Center – June 2020

A Columbia University Irving Medical Center study published in June 2020 found that 99.9% of aerosolized seasonal coronaviruses (that cause the common cold) were inactivated when exposed to far-UVC 222nm light for 25 minutes.

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Kobe University – August 2020

A Kobe University study published in August 2020 suggests that filtered far-UVC light emitted by Care222 lamps can be used to reduce pathogens while people are present.

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Hiroshima University – September 2020

A Hiroshima University study published in September 2020 found that far-UVC 222nm light effectively reduced more than 99.7% of surface contamination of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19.

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All references to “disinfect”, “disinfecting” and “disinfection” refer generally to the reduction of pathogenic bioburden and are not intended to refer to any specific definition as may be used by any governmental or regulatory authority including the U.S. Food and Drug Administration and the U.S. Environmental Protection Agency. Christie CounterAct products with patented Care222 technology are not medical devices and are not to be used as or for medical devices. The pathogen-reducing efficacy of Christie CounterAct products and their use in occupied spaces is dependent on many site-specific factors as well as proper installation and operation within specifications and in accordance with American Conference of Governmental Institutional Hygienist (ACGIH) guidelines. Professional installation is recommended for Christie CounterAct products. “Christie” is a trademark of Christie Digital Systems USA, Inc., registered in the United States of America and other countries. This product uses Care222® technology developed by Ushio Inc. The Care222® is a trademark or registered trademark of Ushio Inc. and Ushio America, Inc.

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