Contributing to Safe Travel with UV-C Technology

By Guest Author: Alessandro Pedote, Co-founder and COO, One.Tray S.p.A

As the sector starts to get back on its feet from the devastating impact of the pandemic, passenger numbers remain curtailed by governmental restrictions, uncertainty, and a lack of confidence amongst travellers. Just as previous events have led to changes in aviation safety and security procedures, new protocols have, and will continue to, emerge in response to COVID-19. Many of these will likely become the norm. As before, safety and security underpin all activities in this sector.

The use of UV-C technology

As part of these new procedures, the use of germicidal ultraviolet light (UV-C) is emerging in the quest to ensure the safety of passengers and staff through additional cleaning regimes and reassure those travelling that it is safe to do so.

UV-C light is used in many industries to provide a chemical-free way to sanitize water, air, or surfaces from bacteria, viruses, and other microorganisms, which can cause infection. UV-C is a particular spectrum of UV light with a frequency ranging from 200–280 nm. Its particularly short wavelength has been proven to have a disrupting effect on DNA or RNA structures, leaving them unable to perform vital cellular functions and thus no longer posing a health risk.

With the outbreak of COVID-19, this technology has become more widely adopted for surface sanitization in different fields, including logistics and transportation hubs. This rapid expansion in use is due to a number of research studies in 2020 that demonstrated the efficacy of this technology against COVID-19, even with relatively low dosage levels. Research references can be found here.

Airports and UV-C sanitization

Airports have focused on implementing new cleaning procedures and processes, and many have been quick to explore the use of UV-C technology as part of their suite of COVID-19 counter measures.

Whilst passenger numbers are currently restricted, airports remain, by nature, busy and close contact environments with many touch points and procedures that those travelling must follow. Clearly this has potential health risks for passengers and staff alike. This element of concern has been addressed immediately by airport operators through exceptional measures such as social distancing, the wearing of masks, and the chemical sanitization of surfaces.

Security lanes and security trays have become a key area of focus as every passenger has to pass through security and handle at least one tray. It is therefore understandable that this unavoidable process has the potential to cause anxiety amongst passengers and security staff about the transference of bacteria and viruses through frequently touched surfaces.

As such, any additional cleanliness would be positively welcomed by all involved and it is in the area of tray sanitization that UV-C technology provides an ideal solution due of a number of its characteristics. Specifically, it is:

• A non-chemical option.
• Safe, as long as the relevant ISO standards are followed, and only certified devices are used.
• Effective in seconds and therefore scalable for high frequency processes such as tray cleaning, without slowing passenger flow.
• Able to sanitize any surface so long as the radiation hits the surface from the correct distance and angle.
• Able to provide visible reassurance to passengers and security staff that the airport is doing all it can to keep them safe.

How effective is the technology?

Whilst this question is often asked within the industry, the answer is dependent on its application. The variables of UV-C efficacy are:

• Exposure time – the longer this is, the higher the dose the surface receives
• Irradiance – measured in W/m2, this defines the radiant power emitted by the UV source
• Characteristics of the target surface – smoother surfaces guarantee a better performance of the UV-C light by reducing micro shadows where microorganisms could remain unaffected

All these variables must be considered when analyzing the efficacy of a UV-C device. In fact, more and more companies are now offering preventive ray tracing simulations to assess the potential level of sanitization, whilst various measurement solutions are on the market to measure the efficacy of the installed UV-C device. These can help airports understand the validity of a device. These solutions are also being used by the suppliers to monitor any degradation of cleaning performance, and should this be the case, to carry out preventive maintenance.

Besides the in-line UV-C devices offered by suppliers of some automatic tray return systems (ATRS), solutions for standalone UV-C cleaning devices are now available and these can also add value to security checkpoints without ATRS. Some suppliers have had their product tested by laboratories to determine the minimum effectiveness and guaranteeing performance ranging from a minimum of 90% to 99.99% sanitization.

Is this technology safe?

Whilst UV-C radiation can be dangerous, hence its effectiveness in killing viruses and bacteria, it is easy to manage and contain. In fact, very thin layers of a variety of materials are sufficient to stop 100% of UV-C radiation, therefore avoiding harmful leakage. Specifically, ISO Standard 15858:(2016) was developed in response to a worldwide demand for minimum safety requirements for products and equipment utilizing UV-C lamp fixtures. Compliance with IS0 15858 ensures that any device is safe and reliable to be used in a crowded environment such as an airport.

A number of airports have either implemented, tested or are currently testing UV-C solutions for tray sanitization, these include:

• Gatwick Airport
• Rome Fiumicino Airport
• Aéroports de Paris
• Milan Linate Airport
• Changi Airport
• Bergamo Airport
• Denver Airport
• Bogota El Dorado Airport
• Auckland Airport

Where to from here?

Of course, UV-C sanitization of trays is not for all. Implementing UV-C based systems will be dependent on a cost/benefit analysis aimed at understanding if the investment is ROI positive from two main standpoints:

• Tangible economics by comparing it to other options for tray sanitization such as regular manual cleaning or chemical based automated tray cleaning devices
• Intangible returns such as passenger and staff satisfaction delivered through a more permanent and visible solution to tray cleanliness.

In whatever way it comes to materialize, UV-C sanitization of trays will likely be a change that the aviation sector will continue to embrace as everyone works to try and bring about a recovery to the sector.