Abstract: A system employing principles of the present invention governs operation of an apparatus by an operator. An embodiment of the present invention comprises means for receiving at least one signal, portable means affixed to the operator for transmitting the signal, and means for inactivating or interrupting the operation of the apparatus should the operator be beyond a pre-specified distance from the controls of the apparatus. The means for inactivating communicates with both the means for receiving and the apparatus, while the means for transmitting sends the signal to the means for receiving during normal operation of the apparatus, e.g., with the operator physically present. Without the presence of the signal, operation of the apparatus is interrupted. One embodiment provides for an emergency override of the system to permit operation of the apparatus without the presence of the signal. Methods of using embodiments of the present invention are also provided.