STS Instruments design and manufacture portable fluorimeters for the instant quantification of organic pollutants in water. Our SMF4 fluorimeter is designed to give a measurement comparable to BOD but instantly not after 5 days wait. As it is instant the measurement is also repeatable. The instrument has uses in the monitoring of outfalls from sewage treatment plants, tracing of pollution down river, misconnections into storm water sewers and in monitoring in-flow to treatment plants to aid energy efficiency. The system can be set up as a remote monitoring unit to cause alarms at set thresholds.