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§ 250.734

250.734(a) – Dual shear rams

Question: Does the regulation require that the shear rams be identical and have identical capacities?

Answer: No, the regulations do not require identical shear rams. The rule requires that both shear rams (i.e., each shear ram) be capable of performing the entire range of listed shearing operations. However, the regulation only requires that at least one shear ram be capable of closing and sealing the wellbore after shearing under MASP, but both must be able to shear at any point along the equipment identified in § 250.734(a)(1)(ii) under MASP.

250.734(a)(1) – Dual shear rams

Question: For rigs that already are configured with dual shear rams, must they comply with the requirement that both shear rams be capable of shearing the newly added component of "appropriate area for the liner or casing landing string" prior to April 29, 2021?

Answer: You are not required to have a second shear ram with the identified capabilities until April 29, 2021. Operators are not prohibited from meeting the dual ram shearing requirements prior to 2021, and BSEE encourages operators to pursue continual improvement toward these standards.

§ 250.734(a)(1); 250.734(a)(1)(ii); 250.734(a)(3)(i); 250.734(a)(3)(ii); 250.734(a)(6)(i); 250.734(a)(6)(ii); 250.734(a)(6)(iii); 250.734(a)(6)(iv); 250.734(a)(6)(v); 250.734(a)(16)(ii)

Question: Do all of the dual shear ram regulations fall under the 5 year compliance timeframe (e.g., the subsea accumulator capacity for the dual shear ram)?

Answer: 30 CFR 250.734(a)(1) requires use of dual shear rams on subsea BOPs no later than April 29, 2021. 30 CFR 250.733(b)(1) requires that surface BOPs installed on floating production facilities after April 29, 2019, comply with the regulatory requirements in 250.734(a)(1), including the requirement to use dual shear rams. Thus, the dual shear ram requirement applies if you install a surface BOP on a floating production facility after April 29, 2019, rather than the five-year timeframe.

250.734(a)(3)(iii) requires that operators have dedicated subsea accumulator capacity for autoshear and deadman functions on subsea BOPs no later than April 29, 2021.

The final rule establishes numerous equipment and process requirements that are ancillary to the operation of dual shear rams as well as to other types of rams or other components of subsea BOPs. For example, § 250.734(a)(3)(i) requires that each subsea BOP have sufficient subsea accumulator capacity to operate each shear ram, the pipe ram, and ram locks and to disconnect the LMRP. BSEE intended such ancillary requirements to take effect at the same time as the requirements for installation or availability of the specific equipment or component that the ancillary equipment or process is designed to operate. So, for example, the accumulator capacity requirement of § 250.734(a)(3)(i) must be met with regard to the dual shear rams within the 5-year compliance timeframe, even if the dual shear rams are installed currently. However, the accumulator capacity requirement must be met with regard to operating the pipe ram within the same 90-day compliance timeframe provided for the requirement that the BOP have one pipe ram (i.e., by July 28, 2016).

The following provisions of the final rule are also directly applicable to dual shear rams; therefore, with regard to operating the dual shear rams, you must comply with these requirements by the April 29, 2021, compliance date:

  • § 250.734(a)(1)(ii) – Shear rams capable of shearing at any point along the identified pipes, tubes, and lines;
  • § 250.734(a)(3)(i) – Subsea accumulator capacity to operate each required shear ram;
  • § 250.734(a)(3)(ii) – Capability to deliver fluid to each ROV function;
  • § 250.734(a)(6)(iv) – Emergency functioning must close, at a minimum, 2 shear rams in sequence;
  • § 250.734(a)(6)(v) – Sequencing of the dual shear rams;
  • § 250.734(a)(16)(ii) – Mitigating compression of the pipe stub between the shear rams.

§ 250.734(a)(3)

Question: Does there have to be enough accumulator capacity located subsea to operate all critical functions open and close?

Answer: No. As required by § 250.734(a)(3), the subsea accumulators must have the capacity “to provide fast closure of the BOP components.” The subsea accumulator capacity must be sufficient to operate (close) each required shear ram, ram locks, one pipe ram, and disconnect the LMRP. That provision does not address the opening of those components. By contrast, § 250.734(a)(4) requires that the ROV panel must have an open function. However, the ROV open function can be performed with fluid supplied from the ROV or another source.

§ 250.734(a)(3)

Question: Does BSEE consider "fast closure" to be satisfied by the requirements outlined in section 7.4.6.5.4 of Standard 53 (close each ram BOP in 45 seconds or less and unlatch the lower marine riser package (LMRP) connector in 45 seconds or less)?

Answer: Yes. The Standard 53 requirements for fast closure for subsea BOPs satisfy this requirement. For surface BOPs, adherence to API Standard 53 sections 6.3.8.4 and 6.3.8.5 would satisfy this requirement.

250.734(a)(3) – Subsea accumulator capacity

Question For operators whose accumulator bank is capable or replenished by the ROV, does capacity sufficient to operate one function at a time (i.e., sufficient capacity to operate the largest consumer) satisfy the rule?

Answer: No. As stated in § 250.734(a)(3), the subsea accumulators must have the required capacity to provide fast closure of the BOP components and to operate all critical functions, without replenishment by an ROV.

250.734(a)(3) – Shared accumulator capacity

Question: Can the entire subsea accumulators system be shared between deadman, autoshear and flying lead if it’s sized to perform the functions required for all these systems? Or are two separate and independent accumulator systems required, one for flying lead, and one for deadman/autoshear?

Answer: No later than April 29, 2021, there must be accumulator bottles dedicated specifically to the autoshear and deadman systems. The bottles may supply both the autoshear and deadman systems but may not supply any other functions.

250.734(a)(4) – ROV functions

Question: Please confirm that the only functions that are required to be opened and closed by the ROV are the shear ram(s), ram locks, one pipe ram and LMRP disconnect.

Answer: This regulation defines the minimum instrumentation of subsea BOPs. The ROV functions required are clearly specified in the regulation: “The ROV must be capable of opening and closing each shear ram, ram locks, one pipe ram, and LMRP disconnect under MASP conditions as defined for the operation.” See also 81 Fed. Reg. 25958 (“BSEE revised final § 250.734(a)(4) to limit the ROV functions to the critical functions which are now specified in that paragraph…”).

250.734(b)(2) and 737(d)(8) – Pressure testing BOP components after repair

Question: Section 250.737(d)(8) requires operators to pressure test affected BOP components following disconnection or repair of any well containment seal.

Section 250.734(b)(2) requires operators to perform a full initial BOP subsea test upon re-latch of the BOP.

These regulations seem to conflict regarding what testing is required upon re-latch of the BOP following a pull to surface for repair.

Please clarify whether the process is to re-test the broken connections (currently what is performed) or whether a full initial latch-up test program is required.

Answer: There is no conflict between the regulations, in that operators can comply with both in appropriate circumstances. For a subsea BOP, when a BOP is recovered to surface, the operator must ensure that the repaired component is pressure tested on surface in accordance with § 250.737(d)(8). After re-latch of the subsea BOP system, a full BOP pressure test is required under § 250.734(b)(2). This is consistent with current practices for retesting following subsea BOP repairs. For a surface BOP, you must pressure test the affected components in accordance with § 250.737(d)(8), but § 250.734 does not apply.

250.734(a)(3)(ii) – Subsea accumulator capability of delivering fluid to each ROV function

Question: Does a high capacity ROV (an ROV that has the capability to meet the fast closure times) meet the capability of delivering fluid to the ROV functions?

Answer: A high capacity ROV would not satisfy § 250.734(a)(3)(ii). That provision requires accumulator capacity located subsea with the capability of delivering fluid to each ROV function. This regulation is intended to provide a means for any ROV (not just a high capacity ROV) located in the GOM to be able to utilize the accumulator capacity and respond to an event.

§ 250.734(a)(4) – timing for ROV functions – Open and Close

Question: The regulation requires an open and close function for the ROV capabilities. This provision has a 90 day compliance period. What should an operator do if more time is necessary to ensure all required functionality?

Answer: BSEE has received information from specific operators indicating that additional time might be needed to avoid adversely impacting current drilling activities and to ensure that this provision can be safely and effectively implemented. To avoid any significant disruption of ongoing drilling activities, BSEE is willing to work with operators and forebear enforcement or compliance actions on a case by case basis, in the exercise of its enforcement discretion, against an operator that demonstrates that it is making good faith efforts to comply with this provision as soon as reasonably possible. No such forbearance will be shown beyond December 28, 2016.

§ 250.734(a)(6)

Question: For EDS sequences, please confirm that if industry has an EDS mode that closes 2 shear rams in sequence, it meets the requirements of this section. The actual EDS mode will be selected based on operational risk assessment.

Answer: Yes, to comply with § 250.734(a)(6), an EDS mode must be able to close two sets of shear rams. The sequencing of the shear rams should be set to function in a reasonable timeframe. The selection of the EDS mode and the specific sequencing of emergency functions should be developed by the operator based on safety considerations.

250.734(a)(6)(ii) – Deadman criteria for activation

Question: Is there a definition for “signal transmission capacity”?

Answer: This is defined as a simultaneous absence of hydraulic supply and control of both subsea control pods.

734(a)(6)(iv) – Shared accumulator capacity

Question: Does this requirement imply that the Deadman/Autoshear and EDS must have the accumulator capacity to shear with both shear rams? Or is the “expected shearing and sealing action” determined by the operator for each system, where one shear ram can shear and the second only seals?

Answer: After defining “autoshear”, “deadman”, and “EDS”, the regulation states that “[e]ach emergency function must close at a minimum, two shear rams in sequence and be capable of performing its expected shearing and sealing action under MASP conditions as defined for the operation.” (emphasis added). “[§ 250.734(a)(6)(iv) requires] both shear rams to close for these emergency functions in order to increase the effectiveness of those emergency BOP systems.” 81 Fed. Reg. 25959. With regard to operating the dual shear rams, you must comply with these requirements by April 29, 2021.

250.734(a)(7) – Acoustic system

Question: Is the acoustic system required to operate the critical functions listed in 250.734(a)(3)(i) or does it only have to comply with API Standard 53?

Answer: BSEE expects an acoustic system to comply with API standard 53.  The acoustic system is not required to undertake the operations listed in § 734(a)(3)(i).  In addition, if an operator chooses to use an acoustic control system as an additional emergency control measure (in addition to the required autoshear, deadman and EDS systems), the operator must demonstrate that the system is functional.  81 Fed. Reg. 25960.