BS PD ISO GUIDE 31:2015 is intended to help reference material (RM) producers in preparing clear and concisedocumentation to accompany an RM. It lists and explains mandatory, recommended and other categoriesof information to be considered in the preparation of product information sheets and RM certificates.This information can be used by RM users and other stakeholders in confirming the suitability of an RMor certified reference material (CRM).This Guide also contains the minimum requirements for a label attached to the RM container.Cross References:ISO Guide 30ISO/IEC Guide 99:2007ISO Guide 30:2015ISO Guide 34:2009ISO Guide 35:2006ISO/IEC Guide 98-3:2008GUM:1995