Digital Refractometer

The petroleum industry is standardized through ASTM methods, and the key is having a refractometer that meets the specifications of ASTM. For Refractive Index(RI) measurements, this mostly means ASTM D1218 and D1747. Compliance with D1218 is for measurement at temperatures between 20°C and 30°C and is mainly used for light hydrocarbons. D1747 is for measurements up to 100°C and is often used for crude oils and other process streams. ASTM is very strict with temperature as these types of samples generally have a very much larger dn/dt value than the water/sugar samples used in food