Piezoelectric sensors are solid state sensors with no internal moving parts to wear or fatigue. Mean Time Between Failure (MTBF) analysis for typical industrial sensors predicts a life of 12 years. However, many Wilcoxon Sensing Technologies sensors returned to Wilcoxon for re-calibration are more than 30 years old and still operating. While many sensors do indeed last beyond a decade, empirical data suggests an average life of approximately 15 to 20 years. If a sensor is continuously operated to the full limits of their environmental specifications, then their life span can be decreased. Sensors exposed to high temperatures (> 200ºF) and rough handling are candidates for earlier failures than those permanently mounted in benign environments.