It is used to accurately measure the thickness of light non-aqueous liquid (LNAPL) or heavy non-aqueous liquid (DNAPL) floating on the groundwater surface, with an accuracy of up to 1 mm.The scale tape and sensor are able to withstand the erosion of oily hydrocarbons, solvents and other contaminants.It has a safety certification from the Canadian Standards Association (CSA) and can be used in reservoirs and areas where explosive gases may appear.