Many stainless purchase contracts specify only the material standard (e.g. A240 or EN 10088-2) and omit the dimensional tolerance standard, leaving thickness, width and flatness disputes without a basis.

US system:

• ASTM A480: general requirements covering dimensional tolerances, flatness, surface, edge condition and packaging; commonly paired with A240. • Thickness tolerances are banded by width and thickness, with standard and tighter classes; flatness (steepness) also has limits.

European system:

• EN 10131: dimensional and shape tolerances for cold-rolled stainless sheet and strip. • EN 10051: dimensional and shape tolerances for hot-rolled stainless strip (continuous rolling).

Practical advice:

1) State in the contract/order: material standard (A240/EN 10088-2/GB 3280) + dimensional standard (A480/EN 10131/GB/T 708). 2) Specify the tolerance class (normal/tighter) and flatness requirement (mm/m). 3) Cut-to-length, slitting and stamping need tighter requirements — agree them separately. 4) Inspect each item against the dimensional standard at delivery and keep measurement records.

In short: the material standard decides what steel it is; the dimensional standard decides whether it can be used. Write both.