Review of IGEM/SR/25 for Use with Hydrogen

This report presents the findings of the initial gap analysis and technical review of IGEM/SR/25, undertaken as a collaborative effort between HSE and DNV GL. The review is intended to help understand the steps which would be involved in updating the standard to include data appropriate for installations using H2 or an H2/NG blend. Furthermore, the report highlights where additional research and updated data applicable to H2 installations is needed to enable development of an H2-specific supplement to the standard.
A review of alternative approaches for area classification is presented. This review is aimed at determining whether existing standards or guidance provide methodologies which could be used as an alternative to IGEM/SR/25 for area classification of systems using either H2 or H2/NG blends. The review covers IGEM/SR/25, IGE/SR/23, EI15, BCGA guidance, BS EN 60079:10:1 (including Quadvent), NFPA 497, API RP 505 and EIGA Doc. 121/14. Some of these are general, like the British Standard BS EN 60079-10-1:2015, while others are industry specific, like IGEM/SR/25 and EI15.
Consideration is given to the methodology that each area classification approach presents for establishing the zone and zone size, with particular focus on how factors such as ventilation and gas buoyancy are accounted for in the methods. The findings of the review indicate that none of the alternative approaches evaluated in the study provide an approach that is suitable for the gas industry for the area classification of gas network installations involving H2 or an H2/NG blend.