3645 Determining separation distances for small-scale hydrogen installations: calculation tool and user guide

Overview:

EI 3645 Determining separation distances for small-scale hydrogen installations: calculation tool and user guide provides a practical framework for determining appropriate on-site and off-site separation distances for small-scale hydrogen installations handling gaseous and liquid hydrogen. Developed to support the early stages of project planning, design and facility layout, the guidance presents recommended hazard thresholds, risk-informed approaches to separation distance assessment and key considerations for the safe siting of hydrogen equipment and infrastructure.

A central component of the publication is the accompanying EI 3645-1 Calculation tool for determining separation distances for small-scale hydrogen installations, an Excel-based tool developed to enable users to estimate separation distances based on specific process conditions, equipment types, inventory sizes and hazard criteria.

The guidance includes detailed instructions for using the calculator, worked examples, explanation of assumptions, interpretation of results and discussion of limitations and uncertainties. Together, the guidance and calculation tool provide a practical, transparent, and consistent approach to supporting hydrogen project developers, designers, operators, regulators and other stakeholders in assessing separation distances and promoting the safe deployment of hydrogen technologies.

The calculator is available to download as a supplementary material from 'My Publications' following purchase.

EI 3645 and EI 3645-1 form part of a wider EI project focused on determining separation distances for small-scale hydrogen installations. Much of the technical basis for both the guidance document and accompanying calculation tool is drawn from the EI 3644 Research report: literature review for determining separation distances for small-scale hydrogen installations, which is available here.