Abstract: An apparatus for protecting the operator's compartment of a piece of heavy equipment in the event of a cave-in is interchangeable with the standard protective structure normally associated with the equipment for roll-over protection. The apparatus includes a plurality of upright and horizontal frame members for forming an enclosure around the operator's compartment. First and second upright frame members in the rear of the enclosure terminate with brackets which may be detachably coupled to the same brackets which secure the standard roll-over protective structure. The upright frame members are also secured to the floor of the operator's compartment by means of additional brackets. An overhead roof section is coupled to and supported by the upper region of the enclosure. The enclosure is provided with at least one side door and first and second escape hatches all of which are hingedly coupled to the enclosure and open outwardly only. The enclosure, doors and escape hatches are covered with expanded metal.