Deployable guard for mobile x-ray system

A boom has an x-ray head attached to one end thereof and the x-ray head has an x-ray source disposed therein. In a docked position of the boom, the x-ray source is disabled. In a deployed position, the x-ray source is enabled. A handle attached to the x-ray head is movable into at least two different positions. A first one of the positions disables the x-ray source while a second one of the positions enables the x-ray source. The handle extends a preselected distance from the x-ray source such that the handle maintains at least the preselected distance between the x-ray source and a subject to be exposed thereby.