ISO 21028-2:2018 specifies the toughness requirements of metallic materials for use at temperatures between −20 °C and −80 °C to ensure their suitability for cryogenic vessels. This document is applicable to fine-grain and low-alloyed steels with specified yield strength ≤460 N/mm2, aluminium and aluminium alloys, copper and copper alloys and austenitic stainless steels.

NOTE For steel materials listed in EN 13445‑2 or EN 13480‑2 or for steel materials and weldings complying with the same fundamental safety requirements, the requirements for prevention of brittle fracture at low temperatures according to EN 13445‑2:2014, Annex B, method 2, or EN 13480‑2:2012, Annex B, method 2 can be applied.