5 days per Battery
Detectors are classic devices for leading expeditions to excitement, fun, and danger. All detectors are black boxes with a pistol grip and an unmistakable business end. Most detectors only give a binary answer via a red light on the casing. The detectors may also yield direction, intensity or number by alterations of the red light. The ref should be ready to improvise and have fun with detectors.
A lie detector may flash red if a lie is detected. Or the brightness of the red light may increase with the severity of the lie. Directional detectors, like mineral detectors, will light up more brightly when pointed in the direction of the source.
Detectors are 90% efficient. They will discover the mutant, detect the lie, or find the bomb 90% of the time. Detectors find the closest detectable thing first.