Pryor Trust Fatal Gas Well Blowout and Fire

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Accident Description

Accident: Pryor Trust Fatal Gas Well Blowout and Fire

Location: Location: Pittsburg County, OK

Accident Occurred On: 01/22/2018 | Final Report Released On: 06/12/2019

Accident Type: Explosion and Fire

Investigation Status: The CSB's final report was released at a news conference in Oklahoma City, OK, on June 12, 2019.

During drilling operations at a gas well in Pittsburg County Oklahoma, a large explosion fatally injured five workers.

Final Reports

FINAL REPORT: Pryor Trust Final Investigation Report

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Recommendations

American Petroleum Institute (API)

2018-01-I-OK-2

Establish and convene a group of experts with drilling, engineering, and instrumentation expertise to discuss methods to achieve widespread implementation of automatic safety instrumented systems that could bring a well to a safe state in the event other operational barriers fail. Publish a technical bulletin discussing the strategies to implementing Blowout Preventer (BOP) safety instrumented systems.

Status: Closed - Acceptable Action

Closed - Acceptable Action (C - AA) - The recipient has completed action on the recommendation. The action taken meets the objectives envisioned by the Board.

Recommendation Status Change Summary

2018-01-I-OK-3

For onshore drilling operations, develop and publish a recommended practice providing guidance on safely tripping drill pipe during (1) overbalanced drilling operations, (2) managed pressure drilling operations, and (3) underbalanced drilling operations. At a minimum, include information on:

(a) Required equipment for tripping operations,

(b) Techniques and procedures for controlling or preventing formation fluid influx, and

(c) Methods to monitor the well and replace the drill pipe displacement volume with drilling fluid (e.g., mud).

Status: Open - Awaiting Response or Evaluation/Approval of Response

Open - Awaiting Response or Evaluation/Approval of Response (O - ARE/AR) - The recipient has not submitted a substantive response, or the evaluation by CSB staff of a response is pending, or the Board has not yet acted on staff recommendation of status.

Recommendation Status Change Summary

2018-01-I-OK-4

Develop a recommended practice on alarm management specifically for the drilling industry based on guidance in ANSI/ISA 18.2 Management of Alarm Systems for the Process Industries. The recommended practice will address the unique dynamic environment of the drilling industry and provide guidance on implementing a state-based alarm system for different operating modes (e.g., drilling, circulating, tripping, etc.). Include International Association of Drilling Contractors (IADC) in the development of this recommended practice.

Status: Open - Awaiting Response or Evaluation/Approval of Response

Open - Awaiting Response or Evaluation/Approval of Response (O - ARE/AR) - The recipient has not submitted a substantive response, or the evaluation by CSB staff of a response is pending, or the Board has not yet acted on staff recommendation of status.

Recommendation Status Change Summary

2018-01-I-OK-5

Develop a new recommended practice or modify an existing recommended practice (e.g. API RP 54 Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations) addressing the protection of rig workers on onshore drilling rigs from fire and explosion hazards in the event of a blowout. The recommended practice will specifically address:

(a) Protecting drilling cabin occupants from blowout hazards including heat, blast overpressure, and projectiles, such as requiring an increased fire rating for the driller’s cabin that would allow enough time for occupants to evacuate during a blowout and fire;

(b) Minimum required evacuation methods from the drilling cabin, rig floor, and mast or derrick in the event of a blowout so that personnel can quickly escape in variable hazard location conditions. For example, floor exit hatches and exits on the driller’s cabin wall opposite the rig floor could provide safe evacuation routes during a blowout and fire; and

(c) Proximity of the Blow Out Preventer (BOP) activation controls with the driller.

The above options could be retrofitted on existing drilling rigs. Additionally, formally evaluate alternative locations for the drilling cabin that establishes a safe distance from fire and explosion hazards (e.g., ground level).

Status: Closed - Acceptable Action

Closed - Acceptable Action (C - AA) - The recipient has completed action on the recommendation. The action taken meets the objectives envisioned by the Board.

Recommendation Status Change Summary

2018-01-I-OK-6

Update API Bulletin 97 Well Construction Interface Document Guidelines to specify that it applies to both onshore and offshore drilling operations.

Status: Closed - Acceptable Alternative Action

Closed - Acceptable Alternative Action (C - AAA)

Recommendation Status Change Summary
International Association of Drilling Contractors (IADC)

2018-01-I-OK-14

Participate in development of the recommended practice describe in recommendation 2018-01-OK-R4 to [American Petroleum Institute] API.

Status: Open - Awaiting Response or Evaluation/Approval of Response

Open - Awaiting Response or Evaluation/Approval of Response (O - ARE/AR) - The recipient has not submitted a substantive response, or the evaluation by CSB staff of a response is pending, or the Board has not yet acted on staff recommendation of status.

Recommendation Status Change Summary
National Oilwell Varco (NOV)

2018-01-I-OK-17

Design the M/D Totco user interface to allow drilling contractors to pre-set different alarms for different operations (e.g., different alarm configurations for drilling, tripping, circulating, and surface operations in a “state-based” alarm system).

Status: Closed - Acceptable Action

Closed - Acceptable Action (C - AA) - The recipient has completed action on the recommendation. The action taken meets the objectives envisioned by the Board.

Recommendation Status Change Summary

2018-01-I-OK-18

Design the M/D Totco electronic drilling data system so that alarm information, including alarm set points, alarm activation log, alarm horn status (on or off), and alarm system status (on or off) is provided to customers.

Status: Closed - Acceptable Action

Closed - Acceptable Action (C - AA) - The recipient has completed action on the recommendation. The action taken meets the objectives envisioned by the Board.

Recommendation Status Change Summary
Occupational Safety and Health Administration (OSHA)
2018-01-I-OK-1
Implement one of the three following options regarding regulatory changes:

(a) OPTION 1: Apply the Process Safety Management (PSM) standard (29 CFR 1910.119) to the drilling of oil and gas wells; or

(b) OPTION 2: Apply the Process Safety Management (PSM) standard (29 CFR 1910.119) to the drilling of oil and gas wells as in OPTION 1, and make the necessary modifications to customize it to oil and gas drilling operations; or

(c) OPTION 3: Develop a new standard with a safety management system framework similar to PSM that applies only to the drilling of onshore oil and gas wells that includes but is not limited to the following:

Detailed written operating procedures with specified steps and equipment alignment for all operations;

Written procedures for the management of changes (except replacements in kind) in procedures, the well plan, and equipment;

A risk assessment of hazards associated with the drilling plan;

A requirement to follow Recognized and Generally Accepted Good Engineering Practices (RAGAGEP);

Development of a Well Construction Interface Document between the operator and the drilling contractor prior to the commencement of drilling activities which at a minimum includes a bridging document and well plan specifying barriers and how to manage them;

The performance and documentation of flow checks using acceptable methods at defined points during the operation for a specified duration; and

A requirement for employee participation, similar to the Employee Participation requirement in the OSHA PSM standard.
Status: Closed - Reconsidered/Superseded

Closed - Reconsidered/Superseded (C - R/S) - Recipient rejects the recommendation and also supports the rejection with a rationale with which the Board concurs. This designation may apply when later facts indicate that the concerns expressed in the recommendation were actually addressed prior to the incident, or when a recommendation is superseded by a new, more appropriate recommendation.

Recommendation Status Change Summary
Pason Systems Corp.

2018-01-I-OK-15

Design the Pason user interface to allow drilling contractors to pre-set different alarms for different operations (e.g., different alarm configurations for drilling, tripping, circulating, and surface operations in a “state-based” alarm system).

Status: Closed - Acceptable Alternative Action

Closed - Acceptable Alternative Action (C - AAA)

Recommendation Status Change Summary

2018-01-I-OK-16

Design the Pason electronic drilling data system so that alarm information, including alarm set points, alarm activation log, alarm horn status (on or off), and alarm system status (on or off) is provided to customers.

Status: Closed - Acceptable Action

Closed - Acceptable Action (C - AA) - The recipient has completed action on the recommendation. The action taken meets the objectives envisioned by the Board.

Recommendation Status Change Summary
Patterson-UTI
2018-01-I-OK-7

Develop either corporate or rig-specific tripping procedure(s) that detail the required equipment configuration for tripping operations. Require that rig personnel visually verify that equipment is lined up as specified in the procedure before beginning the tripping operation. In the procedure(s), specify well-monitoring requirements for wet versus dry tripping operations.

Status: Closed - Acceptable Action

Closed - Acceptable Action (C - AA) - The recipient has completed action on the recommendation. The action taken meets the objectives envisioned by the Board.

Recommendation Status Change Summary

2018-01-I-OK-8

Develop an alarm philosophy and alarm rationalization for rig operations. Based on the alarm philosophy and alarm rationalization, specify necessary alarms, at a minimum, for (1) drilling, (2) tripping, (3) circulating, and (4) rig floor activities (no drill pipe in well). Additionally, develop a policy implementing the alarm philosophy and rationalization.

Status: Closed - Acceptable Alternative Action

Closed - Acceptable Alternative Action (C - AAA)

Recommendation Status Change Summary

2018-01-I-OK-9

Develop a policy that incorporates recommendations in API RP 59 Recommended Practice for Well Control Operations requiring the regular testing of drillers’ influx detection and response skills through formalized drills, for example by “simulat[ing] a gain in pit drilling fluid volume by raising a float sufficiently to cause an alarm to be activated.” In this policy, require that driller response time is monitored in the spirit of continual improvement.

Status: Closed - Acceptable Action

Closed - Acceptable Action (C - AA) - The recipient has completed action on the recommendation. The action taken meets the objectives envisioned by the Board.

Recommendation Status Change Summary
2018-01-I-OK-10
Develop and implement a policy requiring that flow checks be documented, either electronically or with a paper record. At a minimum the documentation will require the reporting of:

Operation during which flow check was performed

Method of performing flow check

Length of time flow check was performed

Result of flow check

Require that the proper authorities (e.g., driller, company man, rig manager) sign or approve the flow check documentation after performing the flow check and before resuming operations. Keep the flow check documentation as part of the well file.
Status: Closed - Acceptable Action

Closed - Acceptable Action (C - AA) - The recipient has completed action on the recommendation. The action taken meets the objectives envisioned by the Board.

Recommendation Status Change Summary
2018-01-I-OK-11

Update the Patterson metrics program to track leading and lagging indicators to measure the effectiveness of the overall safety management system. Specifically focus on measuring the effectiveness of the following safety management system components:

(a) The effectiveness of the flow check policy, including the frequency that flow checks are performed when required by Patterson policy;

(b) The frequency that flow checks are documented and approved as recommended in 2018-01-OK-R10;

(c) The effectiveness of the management of change program, for both equipment and procedural changes, including real-time procedure changes;

(d) The frequency that alarms are set at the required set points;

(e) The frequency that drilling rig alarm horns or the entire alarm system is turned off; and

(f) The frequency that trip sheets are filled out properly.

Status: Open - Acceptable Response or Alternate Response

Open - Acceptable Response or Alternate Response (O - ARAR) - Response from recipient indicates a planned action that would satisfy the objective of the recommendation when implemented.

Recommendation Status Change Summary
Red Mountain Operating

2018-01-I-OK-12

Develop a new policy that a well-specific Well Construction Interface Document be in place before drilling operations begin, as specified in API Bulletin 97 Well Construction Interface Document Guidelines. Ensure the policy requires that the Well Construction Interface Document specifies the technical requirements of the rig equipment and technical qualifications of personnel (e.g., conventional drilling, managed pressure drilling, underbalanced drilling) as well as specifies which barriers must be maintained and the expected response if a barrier is lost.

Status: Closed - Unacceptable Action/No Response Received

Closed - Unacceptable Action/No Response Received (C - UA/NRR) - Recipient responds by expressing disagreement with the need outlined in the recommendation and the Board concludes that further correspondence on, or discussion of, the matter would not change the recipient?s position.

2018-01-I-OK-13

Develop a management of change policy governing real-time changes to operations and the drilling plan. As part of this policy, require hazard analysis and consideration of rig equipment, procedures, and personnel training and qualifications.

Status: Closed - Unacceptable Action/No Response Received

Closed - Unacceptable Action/No Response Received (C - UA/NRR) - Recipient responds by expressing disagreement with the need outlined in the recommendation and the Board concludes that further correspondence on, or discussion of, the matter would not change the recipient?s position.
State of Oklahoma/Oklahoma Corporation Commission

2018-01-I-OK-19

Establish and implement safety regulations requiring entities who design oil and gas well drilling plans for wells in Oklahoma (e.g., operators) and entities who perform the drilling operation (e.g., drilling contractors) to develop and implement the following prior to conducting drilling operations:

(a) Detailed written operating procedures with specified steps and equipment alignment for all operations;

(b) Written procedures for the management of changes (except replacements in kind) in procedures, the well plan, and equipment;

(c) A risk assessment of hazards associated with the drilling plan;

(d) A requirement to follow Recognized and Generally Accepted Good Engineering Practices (RAGAGEP);

(e) Development of a Well Construction Interface Document between the operator and the drilling contractor prior to the commencement of drilling activities which at a minimum includes a bridging document and well plan specifying barriers and how to manage them;

(f) The performance and documentation of flow checks using acceptable methods at defined points during the operation for a specified duration; and

(g) A requirement for employee participation, similar to the Employee Participation requirement in the OSHA PSM standard.

Status: Open - Unacceptable Response/No Response Received

Open - Unacceptable Response/No Response Received (O - UR) - Recipient responds by expressing disagreement with the need outlined in the recommendation. The Board believes, however, that there is enough supporting evidence to ask the recipient to reconsider.

Recommendation Status Change Summary