: The 21st Edition introduced Boarding Shutdown Valves (BSDV) and more clearly defined the differences between slip and mandrel hangers.
: Organizations requiring multi-user access and automatic updates can subscribe via the API Compass Platform.
: This edition marks a formal separation from ISO 10423. Compliance with one no longer automatically implies compliance with the other. api specification 6a 21st edition pdf link
: The specification now mandates stricter bolting requirements, specifically citing API 20E for alloy/carbon steel and API 20F for corrosion-resistant bolting.
As of early 2026, the 21st Edition remains the active standard, though it has seen several updates to correct errors and clarify technical points. : The 21st Edition introduced Boarding Shutdown Valves
: Another major distributor of technical standards where the latest 21st Edition is available for purchase.
: The primary source for purchasing individual copies of the API Spec 6A in PDF or hardcopy. : Another major distributor of technical standards where
API Specification 6A, 21st Edition - American Petroleum Institute