functional standard - Robuta Search

https://www.astm.org/membership-participation/technical-committees/workitems/workitem-wk97960

ASTM International - Standards Worldwide

https://www.festo.com/gb/en/e/about-festo/blog/innovation/sil-61508-safety-for-your-hydrogen-production-id_1884436/

Hydrogen: Functional safety with international SIL standard 61508 in energy-intensive industries and the process industry

https://www.gov.uk/government/publications/project-delivery-functional-standard

The standard sets expectations for the direction and management of portfolios, programmes, and projects in government.