A managed pressure drilling system, used in conjunction with a continuous circulating device to control wellbore pressure, helped an international E&P company successfully drill a difficult section of an deepwater exploration well in Ghana, West Africa, in 2012. A rotating, low pressure sealing device used in drilling operations utilizing air, gas, or foam (or any other drilling fluid whose hydrostatic pressure is less than the formation pressure) to seal around the drill stem above the top of the BOP stack.
In this scenario, the material and configuration of the material used in each sealing element may be selected such that those identified for primary use while pulling casing oscillator the drill string out of the wellbore may be constructed of a more abrasion-resistant material than those sealing elements selected for primary use while drilling.

In future it may be appropriate to promote a system where increased industry access to MPD capabilities would be driven by mandates set by local and international governing bodies as part of their assessment of applications for deepwater drilling permits.
American Petroleum Institute Specification 16RCD (API-16RCD) entitled "Specification for Drill Through Equipment - Rotating Control Devices," First Edition, © February 2005 American Petroleum Institute, proposes standards for safe and functionally interchangeable RCDs.
Furthermore, they have appreciated that use of the higher rated RCD with a higher surface backpressure with a fluid program that disregards pore pressure and instead uses the fracture pressure of the formation and casing shoe leak off or pressure test as limiting pressure factors would be desirable.

Extending these MPD advantages to a broader scope of deepwater wells can offer safety, operational and economic rewards, however equipment deployment can be hampered by the inability of deepwater drilling vessels, originally built for conventional open-to-the-atmosphere circulating systems, to readily accommodate it.
MPD is a ten-year-old technology that keeps drilling pressure at, or slightly above, reservoir pressure, which, it is argued, in most circumstances gives better control of the annular pressure profile throughout the wellbore than under-balanced or over-balanced techniques, where the pressure is maintained below or above that in the reservoir.