The scope of this document is to guide users of the EN 45545 series, particularly EN 45545-2:2020+A1:2023, in the application of these standards in designing and assessing Ni-Cd batteries on board trains for their fire protection measures. The scope of this document excludes any new requirements, considering only the requirements stated by the above listed standards. However, EN 45545 being generic requirements and not specifically referring to Ni-Cd batteries, this guide helps the application for those batteries.