# Positive material identification (PMI)

> Positive material identification (PMI) verifies the chemical composition and alloy grade of a component, weld or fitting non-destructively, usually with a handheld X-ray fluorescence (XRF) or laser-induced breakdown spectroscopy (LIBS) analyser.

- Source: https://amps.global/glossary/positive-material-identification/
- Type: Glossary
- Published: 2026-09-05
- Tags: NDT, PMI, materials

## Key facts

- XRF identifies most alloying elements in seconds; LIBS or optical emission spectroscopy is needed for carbon content
- API RP 578 describes material verification programs for new and existing alloy piping systems
- Prevents low-alloy or carbon steel being installed where chrome-moly, stainless or duplex is specified
- Analysers are verified daily against certified reference materials

Also known as: PMI, alloy verification, material verification.

## How it works

The analyser excites the surface and reads the characteristic spectrum of the elements present, then matches the composition to a grade library. Results are recorded per component with its location, heat number or tag, and any mismatch is raised as a non-conformance.

## Where it is used

Refineries and petrochemical plants, new fabrication and turnaround scopes, valve and fitting receipt inspection, and verification after suspected mix-ups.

## PMI in AMPS

PMI scopes produce many short records against many components. In AMPS every asset and job carries a QR code. Scanning it opens the asset page and the history of jobs performed on it, assets can hold sub-assets, and jobs can be grouped, for example per shutdown. Reports come from your own Word template with client, PO and location data filled in automatically.

## Related pages

- [Hardness testing (HT)](https://amps.global/glossary/hardness-testing/)
- [Traceability](https://amps.global/glossary/traceability/)
- [Non-conformance report (NCR)](https://amps.global/glossary/non-conformance-report/)

## Sources

- [Positive material identification on Wikipedia](https://en.wikipedia.org/wiki/Positive_material_identification)
- [API - American Petroleum Institute standards](https://www.api.org/products-and-services/standards)