IOGP Well Control Incident Lesson Sharing

21-5 - New technologies (e.g. MPD) & human factors vs. well control basics

We monitor IOGP’s ‘Well control Incident lesson sharing’ which is a regular email that alerts the industry to recent incidents with the hope of sharing knowledge and preventing future well control incidents.

IOGP shared well control lesson 2021-5 ‘New technologies (e.g. MPD) & Human Factors vs. well control basics’ on 1 June 2021. This lesson learned relates to the potential risk when introducing new technology.

In this lesson, the well was successfully shut in, but ineffective communication and lack of understanding of new technology resulted in a large influx. The following investigation showed problems relating to training and procedures associated with new types of technology.

We have created a short explanation about how it relates back to IWCF’s Drilling and Well Intervention Pressure Control syllabi.

There has been several well control incidents similar to the one highlighted above. Due to this, in June 2021, IOGP released their info sheet ‘Managing the introduction of new technology in well operations’.  It includes important considerations when introducing new technology including:

  • risk assessment
  • developing a risk response plan
  • defining performance standards, and
  • learning to improve from successes and failures.

Appendix A of IOGP’s info sheet contains a detailed list of 30 new oilfield technologies and suggests possible mitigations.  You can download the info sheet here.


The incident occurred while drilling ahead a 12-1/4” section with MPD in a high angle well (MW 11.2ppg / static underbalance + Continuous Surface Back Pressure). A change in cuttings was observed and the shakers began blinding off. A gas spike at the shakers occurred and the well was Shut In.

Gain detected only when at surface, thanks to shaker overload & gas peak (postmortem gain evaluation to 80bbls).

Well control was properly managed:

  • Control influx being in the riser first
  • Then performed 1st circulation Driller Method though BOP & Choke. Used MPD to evaluate required Equivalent KMW
  • Displace 11.7ppg heavy mud through BOP
  • Isolate kick zone with cement plug through BHA (managed pressure cementing) – abandoned BHA

What went wrong?

Several factors contributed to the well control incident:

  • Unexpected pressurized reservoir in an intermediate section of the well
  • Lack of communication between Geologists & Drillers. Realtime monitoring Sonic was indicating an increase in PP for several hours, data not shared.
  • Continued to drill with significant RCD bearing leakage. Volume of mud leaking was routed to trip tank, jeopardizing the monitoring of the active volume & EKD flow in / out measurement. Contributing to the volume of gain.
  • The potential implications of drilling ahead while LWD indicators suggested pore pressure at ESD/ECD were not identified or considered.
  • Significant RCD Bearing leakage contributed to the incident.
  • Interviewees indicated that well monitoring with MPD is challenging compared with conventional drilling.

Corrective actions and recommendations

PPFG trends to be plotted in real time against the PPFG prognosis used during the planning of the well. Any deviations from the plan need to be communicated to the operation team in a timely manner. Communication protocols need to be established and tested to allow this to happen effectively. Any changes in PPFG need to be evaluated against the design assumptions, and the implications understood by the operations and engineering teams.

The vendor to proceduralize requirements for RCD bearing usage including installed hours before a hard redress and maximum leakage rate.

Document MPD Strategy, including the following:

  • Agree volume monitoring procedures, including alarm settings and monitoring, while the MPD system is in use. The use of an MPD system does not override normal PVT practices and needs to be agreed and communicated ahead of starting drilling operations that utilise an MPD system.
  • Develop a well control training plan to address well control while using an MPD system including competency assessment criteria.
  • Conduct an engineering/HF review of MPD-related HMI i.e. how well monitoring data is presented to stakeholders.
  • Verify that the Drilling Contractor’s MPD Fingerprinting and Tuning procedure is updated with fingerprinting requirements with an emphasis on the training purposes of fingerprinting.

How does this relate to IWCF syllabi?

Human factors, effective communication and the importance of verifying barrier elements are key features of both the Drilling Well Control and Well Intervention Pressure Control programmes.

Below we have listed several syllabus items that touch upon the importance of these topics.

  • Drilling – DR-SF-PNP-01.02.01 / Well Intervention – WI-SF-COM-02.06.01 The need for well control training and assessment

These syllabus items highlight the need to apply critical skills in emergency situations to reduce the severity of well control events.

In the described Lessons Learned, a specific MPD well control plan and competency assessment were not in place.


  • WI-SF-COM-02.03.02 – Well (pressure) control responsibilities – lines of communication, roles of personnel.

Logging while drilling (LWD) data showed a pore pressure increase for several hours before the influx. Lack of communication between two teams meant this went unnoticed.


  • Drilling – DR-SF-PNP-03.01.07 / Well Intervention – WI-SF-COM-05.01.01 – Verification of well barrier elements

Drilling continued with significant fluid leaking from the rotating control device (RCD). The leak was routed to the trip tank which masked the monitoring of volumes and contributed to the size of the influx.

This incident highlights the importance of non-technical skills for crew.


IWCF’s free online awareness course ‘Well Operations Crew Resource Management (WOCRM)’ awareness course focuses on key non-technical skills including:

  • situational awareness
  • decision making
  • leadership
  • communication
  • teamwork, and
  • performance factors.

You can find more information and register for the free, online WOCRM course on our website here.

All IOGP Well Control Incident Lesson Sharings

Visit the IOGP website for a full list of all lessons shared to date: