HEQ explores some real-world applications of ultraviolet disinfection technology.
UVC light energy in the germicidal wavelength range between 200nm and 280nm has an array of applications throughout the field of infection prevention and control, particularly – but not limited to – within the healthcare sector.
HEQ explores some of the use cases where UV disinfection has proved beneficial.
High-touch computer equipment
A 2019 study conducted in Houston, Texas found that automated UVC infection control was able to ‘significantly’ reduce the spread of hospital acquired infections (HAIs) spread through high-touch computer workstation surfaces. The review investigated the cleanliness of computers at nurses’ stations, on mobile carts and in patient rooms; and reported: ‘[These workstations] are rarely manually wiped down or disinfected and there is seldom training or documented procedures around cleaning of computer workstations. Housekeeping, nursing and IT dispute over who is responsible for the computer workstation cleaning, making computer workstations one of the dirtiest places in healthcare, contributing to the prevalence of healthcare associated infections (HAIs) that lead to morbidity, mortality and excess healthcare expenditure.’
The study compared keyboard cultures from 52 high-use workstations at HCA Houston Healthcare Southeast before and after the installation of no-touch UVC disinfection technology. All post-disinfection samples showed 0% presence of all pathogens for which they were tested.
Food safety
Ultraviolet radiation has long been used to eliminate harmful microorganisms from fruits, vegetables and water, with UV treatment deployed to disinfect water supplies in Marseille, France, in 1908 and UV-irradiated milk introduced to the US in 1928. In agrifood, UV radiation is frequently used to destroy surface pathogens on fruits and vegetables.
In early 2020, researchers at Cornell AgriTech, New York, teamed with Norway’s SAGA Robotics to develop an autonomous robot capable of applying UV treatment to wine grapes, in order to defend them from harmful powdery and downy mildew fungi. The mildew spores evolve swiftly and can develop immunity to antifungal sprays over the course of a single season – but they are particularly vulnerable to light radiation. The UV robot, named Thorvald, is programmed to apply equal doses UV radiation to each vine; though the Cornell researchers are working in partnership with academics at Carnegie Mellon University to develop imaging technology which will enable Thorvald to identify and target vines affected by mildew.
Pittsburgh International Airport
Floor-scrubbing robots at Pittsburgh International Airport have been retrofitted with UVC technology to eliminate coronavirus from floor surfaces, in the first such test case in the US. If the pilot programme, developed with the assistance of Pittsburgh robotics firm Carnegie Robotics, is effective, researchers predict it could be rolled out across the USA’s 149 international airports.
Allegheny County Airport Authority CEO Christina Cassotis praised the contributions of Pittsburgh’s flourishing robotics industry to the wider community during the unprecedented crisis od COVID-19, saying: “We have a whole innovation culture that is looking for ways to do things better, especially in the pandemic; and one of the things that we recognised immediately is that while we have to manage the crisis day to day we have to keep a line of sight into the future, to help inspire confidence in travel again.”
PPE disinfection
In the early stages of the COVID-19 pandemic, the availability of personal protective equipment (PPE) became an exceptionally pressing issue for healthcare staff. Recognising the need to enable the reuse of PPE without compromising the safety of workers, a cross-disciplinary team of engineers from Rensselaer Polytechnic Institute in New York fast-tracked the development and production of a disinfection system which deploys UV radiation to sterilise protective face masks in large quantities.
Deepak Vashishth, Director of the RPI Center for Biotechnology and Interdisciplinary Studies, said: “Normally these things take a very long period of time, but given the national situation, I think there is an understanding at all levels that we need to look for solutions which are stable, good, and safe, and are delivered quickly. I think this is an example of where we came together to deliver a solution, and hopefully, this is going to be useful to the healthcare professionals and frontline workers.”
UV in space
As long form space missions become a closer possibility, many researchers have begun to focus on systems which will enable space travellers to eat and drink safely and cleanly while away from Earth for growing periods of time. One such project is the Biocontamination Integrated cOntrol of Wet sYstems for Space Exploration (BIOWYSE) project, supported by the EU’s Horizon 2020 programme, which aims to address the issue of clean drinking water in space.
Astronauts on the International Space Station (ISS) are able to receive regular deliveries of food and water directly from Earth, with cargo spacecraft able to travel to the ISS in around six hours. For longer journeys, however, BIOWYSE is investigating ways to store and monitor water for contamination in real time. The project has developed a fully automated water dispenser which monitors water quality and automatically decontaminates it using UV radiation.
BIOWYSE co-ordinator Dr Emmanouil Detsis said: “We wanted a system where you take it from A to Z, from storing the water to making it available for someone to drink. That means you store the water, you are able to monitor the biocontamination, you are able to disinfect if you have to, and finally you deliver to the cup for drinking. When someone wants to drink water, you press the button – it’s like a water cooler.”
In addition to producing potable drinking water, Detsis said, the machine is able to monitor and disinfect surfaces within the spacecraft which may be wet or damp from spillages or condensation, and which therefore may pose a potential contamination risk: “Inside the closed habitat, you start having the humidity build up and you may have corners or areas where they are not clean, so we developed something that could check these areas in a fast way. The system is designed with future habitats in mind: a space station around the moon, or a field laboratory on Mars in decades to come. These are places where the water may have been sitting there some time before the crew arrives.”
This article is from issue 14 of Health Europa. Click here to get your free subscription today.
