Which action will help to prevent an interruption of the power supply for a vaccine storage unit?

To ensure that a vaccine storage unit remains powered and maintains the required temperature for vaccine efficacy, utilizing a safety lock plug or outlet cover is an effective preventive measure. This action secures the plug in place, minimizing the risk of accidental disconnection from the power supply. Unplugging can occur due to various reasons such as movement around the storage area, the connection becoming loose over time, or even unintentional tugging on the cord. By implementing a safety lock, the likelihood of interruptions to the power supply due to the unit becoming unplugged is significantly reduced, maintaining the integrity of the vaccine supply.

Other options, while they do promote safe vaccine management, do not directly address the primary concern of avoiding accidental power loss. Monitoring temperatures and ensuring backup storage, though essential for contingency planning, do not proactively prevent a power supply interruption. Using outlets with built-in circuit switches enhances safety but does not guarantee the power supply remains uninterrupted if the plug is disconnected. Therefore, using a safety lock or outlet cover is the best action to prevent an unintentional disconnection from the power source for the vaccine storage unit.