Online TOC control for pure water systems using highly efficient “direct surface” UV oxidation with online conductivity measurement. The miniTOC instrument uses the classic flow-through concept for online TOC control. The efficient UV oxidation of organic compounds by the “direct surface” principle in combination with conductivity detection guarantees the high precision of the measured values. The automated functions of SST and calibration facilitate a high standard of safety and minimised operating costs in controlling the water. The system is controlled on the basis of Windows 7 embedded software and through a TFT touchscreen. All data are encrypted and stored in a specific file for each day. The user has no opportunity to manipulate the raw data. This is an easy to use system which brings quality control to your lab at an affordable level. The miniTOC is a valuable accessory for all ultrapure water systems. miniTOC can also be ordered with interval measuring, enabling up to 3 measuring points or loops to be controlled online with just one system. The interval can be configured by the user. The minitoc can be upgraded with an offline module so grab sample can be meassured.