Ground Fault Circuit Interrupters (GFCI) protect your family and coworkers from potentially deadly shocks due to the combination of wet ground and internal shorts in appliances. Even if the appliance’s fuse or circuit blows, it still may have enough power to seriously injure the victim before that power is depleted. This hazard causes up to 66% of the two-thirds of the 300 electrocutions that happen in households every year.