It has been noted in several studies that the COVID-19 viral particles can stay viable on inanimate surfaces for up to 3 days (Doremalen et al. 2020). As the current lockdown conditions are relaxed, there is a danger of second wave of infections due to inevitable increase in the movement of people. While considerable attention has been paid to social distancing, wearing facial masks to reduce the probability of infection transmission, there is a critical need to reduce the chances of infection spread through fomites such as passenger luggage and packages at the airports and train stations. The paper will describe a technology for continuous disinfection system for passengers’ fomites such as luggage and packages at high-volume footfall locations such as bus/train stations and airports. The technology consists of a UV-C-based illumination system inside an enclosed tunnel with an optional spraying system to dispense a variety of disinfectant solutions that are suitable for passenger bags and other luggage, individual packages.
The chief goal of the proposed fomite disinfection system is to minimize the spread of Wuhan corona virus (COVID-19) by disinfecting the surfaces of the luggage. The disinfection systems are very common and use one of the many of the disinfection strategies. The summary of the key disinfection agents and their utility for the current design are summarized in Table 1. Based on these characteristics, ultraviolet-C (UV-C 100–280 nm) radiation is the preferred disinfection agent. Non-foaming soap solutions are also very effective against coronavirus which has a lipid membrane (Gibbens 2020). The UV-C based disinfection technology is commonplace and is applied widely to treat surfaces in hospitals, water disinfection systems, among many applications (Philips 2020a; ICROCHEM laboratory 2020). The UV-C based disinfection works by damaging the DNA/RNA of bacteria and viruses preventing their replication (Poepping et al. 2014; Xiaong and Hu 2013; Beck et al. 2015). Several commercial products use UV-C based disinfection technologies. For example, almost all domestic reverse osmosis systems have a UV module for an additional level of disinfection, and many of the operation theaters and laboratories use UV-C-based surface sterilization strategies.
There are two challenges with the existing commercial products as applied to the fomite disinfection:
Most of the designs available commercially for the disinfection of hospital rooms and other living spaces are open systems and require the movement of people out of the room when the UV-C disinfection process is carried out. This presents a practical problem when applied to the disinfection of fomites and reduces the overall effectiveness of the systems as they need to be operated with continuous supervision.
A second challenge with the existing systems is that most of the systems are designed outside India and are generally expensive when imported. In a price-sensitive market such as India and many other developing countries, the economic effectiveness of the strategy is essential. Additionally, it is desirable to have a system that has a wide range of uses even after addressing the immediate need for the COVID-19 pandemic. There are very few professional open-source designs of any disinfection device that uses UV-C radiation for living spaces.
This proposed system addresses these challenges comprehensively. The proposed system is unobtrusive during its operation and can be operated even in the presence of people in the living spaces. The system design is very modular, has low capital and operating costs.
Fomite disinfection system is modeled on a tunnel-type architecture commonly seen in airports for screening passenger baggage (Fig. 1). The use of UV-C radiation for passenger luggage disinfection can be augmented with a spray system with non-foaming soap solution towards the end of the tunnel. The entry/exit of the tunnels is covered with UV-absorbing flexible plastic curtains. The technology can also be adopted by organizations such as India Posts, Flipkart, and Amazon that handle high volumes of individual packages at their distribution centers. Particular attention was paid to the use off-the-shelf components that are widely available in the market and are produced in India. The estimated timeline for the first prototype is 1 week after the delivery of the components (estimated to be one additional week). The scaleup and mass production can be achieved within 1 month.