Numerous regulatory frameworks are emerging to guide the greenhouse gas (GHG) accounting of hydrogen, yet inconsistencies and gaps remain—especially between EU legislation and international standards. This overview explores the methodological differences between the EU RFNBO regulation and ISO/TS 19870, highlights their implications for certification, data transparency, and international trade, and offers practical recommendations for harmonization.

Drawing from the HydroNet project, it emphasizes the need for digital, flexible, and verifiable solutions to ensure the credibility and scalability of green hydrogen across global value chains.