COD Digestion Vials, High Range, pk/150. It is used in the water laboratories for analysis and research : For determination of high range Chemical Oxygen Demand (COD) the Reactor Digestion method. US EPA approved for wastewater analysis using Hach Method 8000. Range: 20 -1500 mg/L COD. Pack of 150 vials. Digestion Required:Yes. EPA compliant:Yes.