Positive material identification (PMI) is a process used to verify the composition of a material. PMI is commonly used in industries such as manufacturing, construction, and oil and gas, where it is important to ensure that materials meet specific composition requirements for quality, safety, and performance.

PMI is typically performed using spectrometric techniques, such as optical emission spectroscopy (OES) or X-ray fluorescence (XRF), which can accurately identify the elements present in a material and determine their concentrations. The results of the PMI test are used to verify that the material meets the specified composition requirements and to ensure that it is suitable for its intended use. PMI can also be used to identify materials that have been improperly labeled or that have been contaminated or degraded.