A mill certificate, often called a mill test report or MTR, is a document from the producing mill that certifies a material's grade, chemistry or mechanical properties for a specific heat or lot. It is standard for steel. For lumber, grade stamps from accredited agencies and mill paperwork serve a similar traceability role.
Steel: mill test reports
Steel used in metal pallets, rack uprights and beams is normally supplied with an MTR listing the heat number, chemical composition, and mechanical results such as yield and tensile strength against the specified standard. In Europe and many export contracts the EN 10204 framework defines certificate types, with a 3.1 certificate meaning results are validated by the mill's independent inspection department.
Lumber: grade stamps and mill paperwork
Structural softwood lumber is graded under rules published by agencies such as SPIB, and the grade stamp identifies the agency, mill, species and grade. Pallet lumber is often sold ungraded or to pallet-specific rules, so a buyer who needs proof of species, grade or kiln-dried condition usually requests it in writing from the mill or pallet supplier. Heat treatment for export is documented separately through the ISPM-15 program.
When buyers ask for one
Mill documentation is typical for engineered racking, metal pallets for heavy or regulated loads, and projects where a specification names a material grade. Keep certificates with the purchase record so they can be produced in an audit or a damage claim.
Related Terms
- Metal Pallet
- Lumber Grading
- SPIB
- No. 2 Lumber
- Kiln Drying
- Heat Treatment
- Upright Frame
- Rack Load Application
- Browse all glossary terms
Frequently Asked Questions
Do wood pallets come with a mill certificate?
Usually not by default. Pallet lumber is often purchased ungraded or to pallet-specific rules, so there is no standard MTR the way there is for steel. If you need documentation of species, grade, kiln drying or origin, specify it on the purchase order. Export pallets carry the IPPC mark showing ISPM-15 treatment, which is a separate compliance record and not a mill certificate.
What should a steel mill test report show?
A useful MTR identifies the product, the standard or grade it was made to, the heat or lot number that ties it to the material shipped, the chemical analysis and the mechanical test results such as yield strength, tensile strength and elongation. It should also identify the issuing mill. Check that the heat number on the report matches markings on the material or the supplier's packing list.