Locomotives weigh up to 240 ton each. -Rail cars can weigh flom 30 ton (empty) to 140 ton (loaded). Track construction and maintenance equipment, earthmoving plant and haul tiuaks can all weigh l0,s of tons each. When a 200-lb worker 'arguer;' with any of these equipment they lorse. Rail road and yard workers can, literally, be sunounded by these very large, heavy and potentially dangerous pieces of equipment. lt is imperative that the workers are aware of their surroundings at all time and the movement of this equipment relative to their position. When equipment movennent is planned, expected and monitored by the worker then they can respond appropriately to ensure their safety. This situational awareness becomes paramount when the equipment movement is unexpected or if the worker is distracted or is screened from observing the movement by rain, smoke, darkness, etc. What is needed is a device or system that can detect equipment movement that is potentially hazardous to a worker and provide them a warning of that movement, in real time. Such a device, the Moving Equipment Danger Personal Alert System (MEDPAS) is the subject of this proposal.