The role of quality control for bottling companies is of major importance. ETANAP has a modern microbiology lab where, through daily checks of the production and analyses, the unique quality of SAMARIA water is certified. All necessary analyses include the water that is pumped out, the raw materials, the network, the end product as well as the product kept in storage.

Further, on regular time intervals, checks are performed on the drilling facilities as well as on the end product by the Institute of Geological and Mineral Research, and the Department of Microbiology, Food and Water, University of Crete, ensuring the stable chemical composition of the SAMARIA water. Additional samples are sent for analysis to the General Chemical State Laboratory, the NCSR Demokritos and the Greek Atomic Energy Commission (GAEC).