Which is NOT a recommended safety measure for operating electrical tools?

Operating tools in wet conditions is not a recommended safety measure because moisture significantly increases the risk of electrical shock. When operating electrical tools, ensuring a dry environment is crucial to minimize the potential for water to create a conductive pathway that can lead to serious injuries.

On the other hand, keeping hands dry helps to prevent contact with moisture that could pose a danger. Using equipment marked with the UL (Underwriters Laboratories) mark indicates that the tools have been tested for safety, which is an essential aspect of ensuring secure operation. Checking for damaged cords is fundamental to prevent electrical leaks or faults that could lead to accidents. Each of these other measures emphasizes the importance of safety and risk reduction when using electrical tools, making the correct answer clear.