ISO/NP TS 27941

Staged Transition of Producing Oil Fields to Geological CO2 Storage

Scope

This Technical Specification provides guidance, minimum technical requirements, and recommended practices for the staged transition of producing oil fields to long-term geological CO₂ storage sites. It describes planning, assessment, design, operational changes, monitoring, and regulatory considerations necessary to convert portions or the entirety of hydrocarbon production assets into safe, verifiable storage operations.

The document applies to:
• Conventional oil and gas fields nearing end of production life
• Oil fields where enhanced oil recovery (EOR) has occurred or is ongoing
• Brownfield oil and gas assets evaluated for staged repurposing
• Transitions conducted in multi-phase operational modes, including hybrid production–storage periods
The specification does not attempt to define operating conditions for hydrocarbon fields or storage projects but focuses on the juxtaposition of the two operations.