IEC Guide 104:2019(E) is mandatory and defines procedures for the preparation of safety publications in addition to ISO/IEC Guide 51, including the preparation and use of basic safety publications and group safety publications. Also describes the relationship between TCs with horizontal safety functions or group safety functions and product TCs. In the context of this guide, "safety" relates to the safety of persons, domestic animals, livestock and property.
The main changes with respect to the previous edition are as follows:

- alignment with terms and definitions of ISO/IEC Guide 51:2014;

- reference to IEC Guide 108 in the introduction;

- creation of BASIC SAFETY PUBLICATION and GROUP SAFETY PUBLICATION subcategories to clarify the different types of document (requirements, guidance, mandatory test procedures and reference data);

- improved structure: new titles and subclauses;

- addition to the responsibilities of the technical committees (TCs) with HORIZONTAL SAFETY FUNCTION: development of their publications in collaboration with customer TCs and monitoring the use of their SAFETY publications;

- replacement of Annex A and the associated text by reference to IEC Guide 116;

- shortened status statement for publications with BASIC SAFETY PUBLICATION designation;

- addition of the scope items of a PRODUCT SAFETY STANDARD.