Equip your laboratory with ISO 17025 and ISO 17034 Total Acid Number Reference Standards Paragon. Paragon manufactures these fluids to verify sensitive analytical instruments. Technicians use these instruments to determine acid numbers via potentiometric titration. The manufacturer certifies these TAN standards strictly according to ASTM D664 and IP 177. You can easily apply them to other internationally equivalent testing methodologies. The TAN value plays a vital role in the lubricants industry. Laboratories use it as a confirmatory test for new lubricant quality control. It also supports rigorous condition monitoring for in-use lubricants. This total acid number actively indicates the current age of a lubricant. Consequently, this precise data helps technicians optimize the timing of oil changes.