The COVID-19 pandemic has imposed an increasing demand for service robots as a substitute for humans to conduct various types of work, including diagnosis, screening, disinfection, surgery, telehealthcare, logistics, and manufacturing, to reduce the risk of human exposure in contaminated areas.
With these robots, we can control the spread of COVID-19 and other contagious diseases by reducing unnecessary interpersonal communication (or enforcing social distancing). Most countries worldwide have accepted the deployment of robots and have shown the desired effect in restricting the escalation of both infection and asymptomatic infection cases.
Several robots have been employed in the past two years to conduct a series of key tasks and vital functions in hospitals, airports, transportation tools, hotels, restaurants, and communities. Overall, robotic systems are apt solutions for dealing with many interpersonal problems unique to the lockdowns of the pandemic.
Why UVC disinfection robots?
Depending on the material it was attached to, the COVID-19 virus can survive on an inorganic surface for several days or even weeks. In addition to human-to-human proximity contact transmission, this could cause a healthy person to become infected.
The majority of indoor disinfection in contaminated areas, such as hospitals and quarantine hotels, is done by humans using chemical disinfectants. This significantly increases the chances of a healthy person contracting the highly contagious virus. Due to the consistency of each disinfection in surfaces like elevator buttons, door handles, and handrails, manual cleaning or disinfection may be insufficient to eliminate pathogens from contaminated surfaces. It is very unreliable and time-consuming. That is why this cleaning method is poorly suited for warehouses, shopping centers, and other places with a high density of people.
The best alternative today is the use of autonomous or remote-controlled disinfection robots that can facilitate safe, fast, and effective disinfection. One disinfection method used in these robots is ultraviolet-C (UVC) lights, which do not have the disadvantages of conventional disinfectants such as peroxyacetic acid, chlorine dioxide, hydrogen peroxide, etc.
UVC light with a wavelength from 220 to 300 nm has germicidal properties, particularly bacteria and viruses. It is used by several mobile robots developed by TMiRob, UVD Robots, MIT, and other companies.
Disinfection robots using UVC irradiation are an enhancement to standard cleaning and disinfection, reducing the microbial environmental burden and potentially mitigating the risk of acquiring healthcare-associated infections (HAIs).
Current robots for UVC disinfection can be divided into mobile and non-mobile. Non-mobile disinfection robots are stationary installations with UVC lamps, UV cleaner re-circulation systems, and others. They can clean only air in a small area near the device. They cannot sanitize a large space. That’s why mobile, autonomous robotic systems are gaining popularity in numerous ﬁelds. Autonomy and mobility give several key advantages. Robots equipped with UVC lamps are most effective when implemented autonomously.
Things never told about UVC disinfection robots
Ultraviolet-C (UVC) irradiation deploying autonomous disinfection robots are increasingly advertised to complement standard decontamination procedures with concurrent reduction of time and workload. Despite their increasing use and demand, the effectiveness of UVC disinfection robots is still disputed.
According to experts, there is no existing work exploring the effectiveness of disinfection robots in relation to SARS-CoV-2 and other viruses. The evidence of the impact of UVC is also limited. Although some studies have identified some positive trends and demonstrated a reduction in surface contamination, both UVC light and chemical-based disinfection methods (most commonly hydrogen peroxide vapor) does not demonstrate any significant impact on reduced infection rates in health care settings. UVC light needs to touch a surface to be effective, and its effectiveness reduces with distance.
The UVC robot may require many attempts until it can fully carry out the disinfection process. Besides, interventions by the operator are necessary due to initial programming imprecisions, furniture that had accidentally been moved during routine operations, detection of movement during an ongoing disinfection cycle, or loss of internet connection. Deploying the current generation of UVC disinfection robots is, therefore, unlikely to be of major benefit.
In addition to concerns around effectiveness, these devices are expensive at between $30,000 and $135,000 per unit, and organizations need to train staff to deploy and control them. Besides, UVC light can be dangerous to human health, so people typically need to leave while the robot cleans the room.