Abstract
The objective of this study was to evaluate both condensing (wet) and non-condensing (dry) vaporous hydrogen peroxide (VHP) technologies for decontaminating a worst-case scenario Class II biosafety cabinet. A 23-year-old Class II, type A2 biosafety cabinet equipped with loaded HEPA filters and an inoperable blower was used for this study. Biological indicators were placed at various locations within the cabinet, including between the pleats of supply and exhaust HEPA filters, to assess the success of the decontamination processes. A variety of decontamination program cycle parameters in combination with two different routes of VHP introduction and minor biosafety cabinet preparations were assessed. Initial decontamination attempts using routine program cycles failed (at least one biological indicator grew upon incubation); however, program cycles consisting of modified parameters and BSC preparations resulted in successful (all the biological indicators were inactivated) and repeatable decontaminations. This study concludes that VHP, either wet or dry, could be used to decontaminate an entire biosafety cabinet only if appropriate and thoroughly validated decontamination processes are employed.