[en] A research project, sponsored by the EPRI used metal impact theory and experimental data to develop a quantitative description of loose part signals as a function of impact, signal transmission, and detection properties. These signal properties were used to develop recommendations for the number, location, and attachment of sensors, and methods for signal processing, recording, impact response calibration, system surveillance, and signal interpretation. Technical considerations and experience link these systems to combined applications for component vibration and rotating equipment monitoring. (orig./HP)