ISO 24021-1:2022

Overview

ISO 24021-1:2022 - Light gauge metal containers - Vocabulary and classification - Part 1: Open-top cans and ends, is an ISO international standard that defines terminology and establishes a classification for open-top metal cans and metal ends used for food and beverages. It applies to containers made from tinplate, electrolytic chromium/chromium‑oxide coated steel or aluminium‑alloy plates with a maximum thickness of 0.49 mm. The standard provides a unified vocabulary and a classification scheme (see Annex A) to improve clarity and reduce trade barriers in the light gauge metal container sector.

Key topics and technical content

This document focuses on standardized definitions and classification rather than prescriptive performance tests. Major technical topics covered include:

• Raw and processed materials: terms for tinplate, electrolytic tinplate, coated tinplate, aluminium alloy and laminated materials.
• Manufacturing techniques: definitions for can body, flanging, drawing, necking, roll‑forming, embossing, seaming (double seam), seaming roll/chuck/rail, sealing and easy‑open features (tab, score, rivet).
• Seam and closure terminology: seam height/width/thickness, body hook, cover hook, countersink depth, length/rate of overlap, seam gap.
• Quality and defects vocabulary: wrinkle rating (WR), tightness rating (TR), juncture/cover/body hook butting, false seam, jumped seam, welding defects (pin hole, puncture), score defects and other seam faults.
• Evaluation terms: enamel rate value (ERV), splash, compound and sealing gasket definitions.
• Classification: informative Annex A provides a classification framework for open‑top cans and ends to support consistent identification and communication.

Practical applications

ISO 24021-1:2022 is intended to be used where consistent terminology and classification are essential:

• Specifying product requirements in procurement documents and technical specifications for food and beverage packaging.
• Creating clear design and manufacturing documentation for can manufacturers, converters and metal‑packaging suppliers.
• Supporting quality assurance, inspection and laboratory reporting by providing agreed definitions of defects, seams and ratings.
• Aiding machine manufacturers (seamers, sealers) and tooling suppliers to align terminology with customers.
• Facilitating international trade, regulatory communication and standardization work by preventing ambiguity in product descriptions.

Who should use this standard

• Can and end manufacturers, packaging engineers, QA/QC inspectors, procurement specialists, regulatory bodies, testing laboratories and standards committees.

Related standards

• Other parts of the ISO 24021 series and documents produced by ISO/TC 52 (Light gauge metal containers) covering additional container types and complementary terminology.