The disinfection of the air with UV-C is performed by irradiating the upper-room air only, the whole room when unoccupied, or the air flowing inside the air-handling units. The study conducted by McGinn et al. demonstrated the feasibility of using a UV-C robotic system to disinfect both air and surfaces in a radiology environment, where it was two and four times faster than currently used chemical approaches [

A prospective open-labelled cross-over study was conducted in a -bed teaching hospital in Italy from April to June . To evaluate the effectiveness of the UV-C disinfection robot in reducing environmental contamination, sampling was performed in four different critical areas: single occupancy ward room, intensive care unit (ICU) isolation room occupied for a minimum of h, and operating theaters (OTs).

In our study, we evaluated the efficacy of the UV-C treatment only on the reduction in mesophilic growth that mainly represents human contamination, but not on specific pathogens of interest; however, the reduction was very significant, suggesting that this system can easily eliminate pathogens as well. We have previously demonstrated that the adoption of an automated UV-C-disinfection robot in the enhancement of SOP in high-risk settings was successful in reducing pathogens on high-touch surfaces, improving the patient&#x;s safety [

Our study has some limitations. Firstly, the non-homogeneous sampling for all of the settings, where a greater number of analyses were dedicated to the OTs rather than the ICUs or patient rooms: it was not always possible to proceed with the UV-C treatment at the patient discharge because trained personnel were limited and not always available. This problem underlines the importance of having dedicated personnel identifiable as that of the outsourced cleaning company. The use of new technologies could in fact be included in outsourcing contracts as an improvement action in the event of non-compliance in the cleaning service. These personnel could be adequately trained not only on the cleaning protocols to be adopted but also on infection control issues.

Moreover, it would be important to evaluate the advantages of implemented cleaning and disinfection protocols with the use of UV-C devices in areas hosting fragile and vulnerable patients, e.g., in intensive care units. The principal limitation is the continuous presence of people in this type of setting. For this reason, it would be worth evaluating strategies aimed at protecting the patient&#x;s safety using protective devices, which may be evaluated for human security during UV-C emission at specific dosages and times.