Two Year Evaluation of Nonthermal Plasma Technology to Reduce Microbial Contamination and Improve Air Quality at a Large Casino

Bacteria and viruses are an increasing health challenge, particularly for casinos, given the density of occupation in common and gaming areas. Guests may interact with gaming equipment for extended periods of time with high levels of touch on common surfaces. Several government agencies agree on the importance of antimicrobial mitigation, including The White House. At their recent event, ‘Let’s Clear the Air on COVID’, it was emphasized that improving indoor air should be a high priority to prepare for existing and future pandemic threats. This study evaluates the efficacy of nonthermal plasma technology in reducing surface and airborne microbial contamination in a 400,000 sq ft active casino gaming space. Traditional air filtration and disinfection efforts of casinos result in substantial labor, material, and energy costs. After an initial pretreatment testing on July 2, 2020, the Casino Property was treated with gas-phase H2O2 generators utilizing a nonthermal plasma technology provided by AIRPHX. All areas tested showed significant reductions in airborne and surface microbes. Substantially lower CFU counts were achieved in the post-treatment samples compared to those of the exterior samples and the pretreatment samples. As documented in this study, the technology tested appears to offer proactive disinfection in large, highly trafficked facilities. The long-term, real-world nature of this study supports its relevance as a disinfectant in indoor environments and adds additional validation to already published independent studies in controlled lab settings. Keywords: nonthermal plasma, indoor air quality, air disinfection, gas-phase H2O2 generator, air sanitization