This document has been prepared by Working Committees NA 062-06-62 AA "Prüfung von Schmierfetten" ("Testing of lubricating greases") and NA 062-06-13 AA "Molekülspektrometrie" ("Molecular absorption spectrometry") at Technical Section Standardization of Petroleum, Fuels, Lubricants and Related Products (FAM) of the Materials Testing Standards Committee (NMP) at DIN. This document aims at defining the specific analytical characteristics and procedural steps that shall be particularly considered when performing analysis of greases by infrared spectrometer, where those deviate from proven working techniques in the field of petroleum. This document has been drafted so as to allow the herein specified general working principles to be adopted and cited by other Technical Sections dealing with analysis by infrared spectrometry. This document establishes specific conditions for the recording and qualitative interpretation of infrared spectra of unused greases and, in particular, the suitable procedural steps for filling and cleaning the cuvettes. The analysis by infrared spectrometry (IR) can only be performed together with DIN 51451.