Any discontinuity in the power cords of electrical devices can lead to electric shock, injury, and even death. This article presents a portable device that, when placed in the proximity of handheld tools, prevents such injuries. The principal operation of this device is based on electric and magnetic field meters and display segment LEDs. When the grounding conductor of a portable tool with a metal enclosure is broken, the electric field around it is increased. In the same way, when the neutral conductor is broken, the magnetic field is increased. The device detects any variations in electric or magnetic fields and displays a warning signal for alert.