An elimination-absorber monitoring system addresses diaper-monitoring problems with a unique, low cost, multi-layer disposable sensor structure that absorbs small volumes of urine, yet allows most urine volume to flow unimpeded through it, and into the diaper below. When connected with a reusable, miniature monitor/indicator unit, the sensor presents a clear and on-going change of measurement condition upon experiencing a rapid influx into the diaper of a significant volume of urine, and/or upon a significant reduction in the available absorbency of the diaper's top surface. The sensor additionally provides recessed, protected elements for similarly presenting a clear and on-going change in measurement condition upon experiencing the presence of fecal matter. Further provided is the monitor unit employing narrow, widely-spaced, fast rise-time, fast transition-time pulses for conductivity measurement and alarm activation. The monitor and sensor are interconnected and attached to a diaper by particularly effective and unique means, and the monitor is equipped with a highly intuitive and convenient control interface, as well as improved assemblies for the transmission of audible and visual alarm indications. Also described is a convenient test-strip device which, when connected to the monitor/alarm unit of the system, can selectively simulate either a soiled or unsoiled elimination-absorber/sensor for test, caregiver-training or demonstration purposes.