Plastic wraps choosing and the cleaning interval applied in the disinfection of elevator buttons

Fomite transmission has always been a possible route for different pathogens spreading within the facility. To cover the elevator buttons with varying plastic wraps was generalized applied, especially during the COVID-19 pandemic. However, the durability of different wrap membranes, the aerobic bacterial count of different button locations, and the adequate interval for surface cleanliness remain unknown.

Materials and methods:
A total of six different plastic covers, including polyethylene (PE), polymethylpentene (PMP), polyvinyl chloride (PVD), polyvinylidene chloride (PVDC), the thermoplastic polyurethane (TPU) keyboard cap, and the polyethylene terephthalate-ethylene vinyl acetate (PET-EVA) laminating film were tested. Adenosine triphosphate (ATP) bioluminescence assay was introduced to measure the environment cleanliness of the four main elevators in a regional hospital.

The PVDC wraps had the best durability among elevators with similar using frequencies, compared to the PMP, PVD, and PVDC ones. PVDC wraps also had the lowest detectable ATP level within those six tested materials. Regarding the different button locations, the highest ATP values were detected in door-close buttons (p< 0.05, vs. first-floor buttons; p< 0.001, vs. other floor buttons), followed by door-open buttons (p< 0.05, vs. other floor buttons), and first-floor buttons. This trend was unchanged whether in different sampling intervals or sampling dates. Despite been disinfected with sodium hypochlorite, the ATP level of buttons raised rapidly after touching and became more prominent after three hours (p< 0.05, vs. one hour or ten minutes).

The PVDC plastic cover provides more protection for elevator buttons, while the bleach is used for environmental cleaning. More accurate and precise disinfection of the most frequently touched elevator buttons at an interval not longer than three hours may be warranted.