Polymer-based businesses face productivity losses due to unwanted particles, gels, agglomerates and other contaminates. The ability to detect, reduce and eliminate them directly impacts product properties, product quality, recycle, waste generation, manufacturing equipment downtime and human resources. A commercial instrument which has the capability to monitor (detect, size and count) these contaminates is the Kayeness/Flow Vision Polymer Event Detector and its replacement the Continuous On-Line Analyzer (COLA 2000). Both instruments use visible light in a forward light blocking technique to obtain images of events that are analyzed for size and number count. Probes that withstand high temperature and pressure may be installed in a number of process locations. Examples of off-line and in-line applications will be discussed.