Even the smallest traces of oil can cause significant issues in water quality. Hach® probes continuously monitor surface waters, process water, and industrial water for any signs of mineral oil contamination. Using a highly sensitive UV fluorometer immersed directly in the medium, which is directly immersed in the medium, they provide reliable and long-term stable hydrocarbon monitoring. The system compensates for intensity fluctuations in the flash lamp and automatically eliminates any daylight influences.