BOP

A blowout preventer (BOP) is a large valve at the top of an oil drilling well that may be closed by the drilling crew. By closing this valve (usually operated remotely via hydraulic actuators), the crew can avoid overpressure from fluids entering the wellbore and threatening the rig. By closing the BOP, the drilling crew usually regains control of the reservoir, preventing explosive pressure release, and procedures can then be initiated to increase the mud density until it is possible to open the BOP and retain pressure control. "Mud" is a term familiar to those of us who work consistently in offshore settings or on vessels. Mud refers to the drilling fluid used in drilling operations. The invention and use of BOPs were instrumental in the end of oil gushers, which were dangerous and costly.

BOPs come in a variety of styles, sizes and pressure ratings. BOPs are critically important to the safety of the crew, the rig and the wellbore itself. Therefore, they must be inspected, tested and refurbished at regular intervals. Experts must assess risks at each individual location of a BOP to determine when and how the device should be repaired or changed out. Local practice and well type also contribute to the overall decisions regarding safe practices with BOPs. Of course, as maritime lawyers know, there are also legal requirements for BOP testing and maintenance. This testing can range from daily function testing on critical wells to monthly or less frequent testing on wells thought to have low probability of well control problems.

The drilling crew that works with BOPs and operate the offshore drilling rig typically consists of roustabouts, roughnecks, floorhands, lead tong operators, motormen, derrickmen, assistant drillers, and the driller. Since drilling rigs operate around the clock, there are at least two crews (twelve hour work shifts called tours, more common when operating offshore), or three crews (eight hour tours, more common onshore).

OSHA, the federal agency charged with occupational safety, has a web page devoted to safe drilling practices and on this page the agency lists suggestions. They list blowout prevention as a concern and suggest the following to assist with making offshore drilling work safer:

1. Appropriate training for tasks performed, including pressure concepts and calculations, well control procedures, and regulatory information (to name a few).
2. Use of appropriate well control equipment including specification, installation and maintenance.
3. Monitoring and maintaining the mud system because each part of this system must function and be in good repair to maintain well control. This would include properly training crewmembers in monitoring and well control procedures.
4. Testing BOPs
5. Properly maintain the surface control system
6. Wear appropriate personal protective equipment
7. Implement injury awareness training