Total Acid Number (TAN) Miligram of KOH required for nutralization of 1 gram of oil sample. Miligram of KOH required per gram of oil sample or per 1 gram of oil sample. LTV = Low Tan Value MTV = More Tan Value Total Acid Number (TAN) Total Acid Number (TAN) is a key measure used to determine the acidity of petroleum products, lubricants, oils, and other industrial fluids. It refers to the amount of potassium hydroxide (KOH), in milligrams, required to neutralize the acidic components in one gram of the sample. TAN is essential for monitoring the quality, stability, and condition of oils since acids present in fluids can lead to corrosion and oxidation, which damage machinery and equipment over time. Importance of TAN Measurement Corrosion Prevention: Acids in oils, such as sulfuric or organic acids, can cause corrosion in engines, pipelines, and other mechanical systems. High TAN levels i...