Abstract: An apparatus and method for detecting a surgical implement retained within a surgically exposed human body cavity, include tagging means adapted to be attached to a surgical implement insertable within a human body cavity and including means for receiving an electromagnetic signal and converting it into electric current (pulses); and means to conduct said current (pulses) to the internal human (or an animal) body where said medical product is used; and means to transmit said electromagnetic signal; and detecting means including reception means for receiving a signal from a tagging means, detector means connected to the reception means for sensing a signal received from a tagging means. The envelope of the induced RF wave is demodulated, thus allowing the voltage at output to vary at a significantly lower frequency. In the event such pulses are sensed, a sensory alert is actuated and corrective action taken.