This Guide is intended to help producers to prepare clear and concise certificates to accompany certified reference materials. Such certificates, while maintaining their essential character, should help to provide, in summary form, all the information needed by the user of the reference material.
ISO Guide 31:2000 history
2015ISO Guide 31:2015 Reference materials - Contents of certificates, labels and accompanying documentation
2008ISO Guide 31:2000 Reference materials - Contents of certificates and labels
1981ISO GUIDE 31:1981 Contents of certificates of reference materials