Plasma-activated mist (PAM) is a novel method that has shown potential for the decontamination of fresh produce. In this study, we evaluated the decontamination of Escherichia coli O157:H7 on nutrient agar plates and various types of fresh produce, both individually and stacked layers. Single pieces of kale achieved a notable 3-log10 reduction, while spinach and lettuce showed reductions of over 1.5-log10, and strawberry exhibited the lowest reduction of 0.8-log10. The efficacy on stacked multiple layers of spinach, kale, and strawberry was shown to achieve just over 0.9-log10 reduction of E. coli but always worse than the inactivation observed on a single piece. A mathematical diffusion model was employed to explore scaling up PAM for industrial applications, particularly on stacked spinach layers.