LI class refers to the different types of testing that can be performed. When a lot is inspected, the LI class identifies which of these different tests are to be conducted on the lot. Some examples of LI classes are density, material strength, color, average molecular weight, and pH level.
The LI class is used to connect an inspection to the applicable prerequisites. These include measurement unit, measurement instrument, laboratory, and measurement method. The basic data specified in an LI class is used in the LI specification.