A system for use of acoustic reflectometry in nasogastric enteral access devices, the system comprising: a nasogastric enteral access device ; a sound generator to emit sound into the nasogastric enteral access device ; at least one sound receiver to detect amplitudes and timings of returning acoustic reflections at a plurality positions of a distal end of the nasogastric enteral access device within a body; and a reflectometry device having at least one processor and a memory that is accessible to the processor configured to analyze amplitudes and timings of the returning acoustic reflections and to detect a positive amplitude deflection in the acoustic reflections at a first position of the distal end of the nasogastric enteral access device within the body, the positive amplitude deflection in the acoustic reflections being from the distal end of the nasogastric enteral access device , wherein the reflectometry device configured to indicate, based on the detection of a positive amplitude deflection in the acoustic reflections at a first position of the distal end of the nasogastric enteral access device within the body, that the distal end of the nasogastric enteral access device is above or at the lower esophageal sphincter, the positive amplitude deflection in the acoustic reflections being from the distal end of the nasogastric enteral access device ; wherein the nasogastric enteral access device comprises a plurality of ports, and wherein the acoustic reflectometer is acoustically coupled to a first of the plurality of ports and a second or more of the plurality of ports not coupled to the sound generator are occluded by plugs to prevent extraneous acoustic reflections arising from the ports from interfering with the reflections arising from within the nasogastric enteral access device and cavities in which the nasogastric enteral access device is inserted. a nasogastric enteral access device ; a sound generator to emit sound into the nasogastric enteral access device ; at least one sound receiver to detect amplitudes and timings of returning acoustic reflections at a plurality positions of a distal end of the nasogastric enteral access device within a body; and a reflectometry device having at least one processor and a memory that is accessible to the processor configured to analyze amplitudes and timings of the returning acoustic reflections and to detect a positive amplitude deflection in the acoustic reflections at a first position of the distal end of the nasogastric enteral access device within the body, the positive amplitude deflection in the acoustic reflections being from the distal end of the nasogastric enteral access device , wherein the reflectometry device configured to indicate, based on the detection of a positive amplitude deflection in the acoustic reflections at a first position of the distal end of the nasogastric enteral access device within the body, that the distal end of the nasogastric enteral access device is above or at the lower esophageal sphincter, the positive amplitude deflection in the acoustic reflections being from the distal end of the nasogastric enteral access device ; wherein the nasogastric enteral access device comprises a plurality of ports, and wherein the acoustic reflectometer is acoustically coupled to a first of the plurality of ports and a second or more of the plurality of ports not coupled to the sound generator are occluded by plugs to prevent extraneous acoustic reflections arising from the ports from interfering with the reflections arising from within the nasogastric enteral access device and cavities in which the nasogastric enteral access device is inserted. <EOS>