**1.3 The evolution of disinfection systems**

One growing understanding is that the application method of a disinfectant plays a critical role in the success of the disinfection results. While some of the most common spray and wipe surface disinfectants have been in use for decades, there are challenges to their application which can result in inconsistent or ineffective

results. Adequate distribution and required contact time are difficult to achieve on a consistent basis by hand application methods, especially in large spaces with high ceilings and complex surface profiles. These accessibility issues and failures may result in inconsistent and incomplete elimination of surface contamination [13]. To address inherent inconsistencies in manual disinfection and to provide alternative methods of delivery, various technologies have been applied. Those technologies include fumigation with formaldehyde, chlorine dioxide gas, fogging of hydrogen peroxide as vapor, silver hydrogen peroxide systems, and hybrid hydrogen peroxide systems. Their gaseous and vaporous form allows access to, and contact with, surfaces that spray and wipe methods alone often cannot access. Automated systems have taken these chemicals with known disinfectant action and paired them with dispersion devices, aiming to deliver an appropriate contact time and maximize surface exposure. These systems automate much of the disinfection process, helping to remove human error and mitigate safety concerns from contact with potentially caustic chemicals. In particular, H2O2-based systems have become a front-runner among automated high-level disinfection technologies due to H2O2's effectiveness, material compatibilities, lack of chemical residues, and increased safety over other technologies such as formaldehyde or chlorine dioxide gas [14–18]. When applied in multiple life science environments, H2O2 fogging is well documented to have efficacy against numerous viral pathogens and has seen a rise in use in environments where thorough efficacy and decontamination of a room and its contents are needed [19–22].
