API 16Q provides requirements for the design, selection, operation, and maintenance of typical marine riser systems for floating drilling operations from a mobile offshore drilling unit (MODU) with a subsea blowout preventer (BOP) stack. Its purpose is to serve as a reference for designers, for those who select system components, and for those who use and maintain this equipment. It relies on basic engineering principles and the accumulated experience of offshore operators, contractors, consultants, and manufacturers.

Each owner and operator is encouraged to observe the recommendations outlined herein and to supplement them with other proven technology that can result in a more cost-effective, safer, and/or more reliable performance.

The marine drilling riser is best viewed as a system. It is necessary that designers, contractors, and operators realize that the individual components are recommended and selected in a manner suited to the overall performance of that system. For the purposes of this document, a marine drilling riser system includes the tensioner system and all equipment between the top connection of the upper flex/ball joint to the lower flex joint. However, it specifically excludes the diverter. Also, the applicability of this document is limited to operations with a subsea BOP stack.

Sections 1 through 7 are applicable to most floating drilling operations. In addition, special situations and topics are addressed in Section 8 dealing with deepwater drilling, cold weather environments, riser collapse, hydrogen sulfide (H2S), well testing, and managed pressure drilling (MPD).