A wet/dry utility vacuum with a canister, a powerhead assembly with a fan, a shut-off device that prevents the fan from drawing liquids into the fan inlet when a volume of the liquid in the canister exceeds a predetermined volume. The powerhead assembly includes a controller that permits the utility vacuum to be operated in a desired power mode so that the user may employ either an AC power source or a DC power source, such as a battery pack, for example. In some applications, the battery pack may be interchangeable with the battery packs of various cordless tools, including drill/drivers and saws. A tool set and a method for operating a battery-powered tool set are also provided.