NTSB Safety Recommendation P-26-007

NTSB safety recommendation P-26-007.

TO THE ATMOS ENERGY CORPORATION: Require your technicians who identify but do not repair a belowground natural gas leak to immediately notify people near the unrepaired leak that (1) the hazard potential of a leak can change over time, and (2) they should evacuate and then call 9 1 1 and Atmos Energy Corporation every time they smell natural gas odorant.

Priority: CLASS II

Overall Status: Open - Initial Response Received

Issued Date: 2026-03-26

Adopted Date: 2026-03-12

Synopsis: This report discusses the January 2024 natural gas-fueled explosions and fires at two separate homes in Jackson, Mississippi, which occurred 3 days apart, collectively resulting in one injury, one fatality, and three destroyed homes. Safety issues identified in this report include compression coupling leaks, insufficient leak management program, inadequate distribution integrity management program, ineffective public awareness program, and absence of natural gas detection alarms in buildings.

Probable Cause: The National Transportation Safety Board determines that the probable cause of the two explosions at two separate homes in Jackson, Mississippi, was the service-line pipes partially pulling out of the compression couplings, likely because of soil movement (shrinking and swelling), creating natural gas leaks that Atmos Energy Corporation identified and left unrepaired for at least 8 weeks, which enabled gas to migrate to the nearby homes and ignite. Contributing to Atmos Energy Corporation’s failure to prevent the accidents were the operator’s: (1) insufficient leak management program, which did not determine appropriate monitoring timelines for leaks in adverse-soil conditions; (2) ineffective public awareness program, which did not adequately educate the public or emergency response officials on how to respond to a suspected natural gas leak; and (3) inadequate integrity management program, which did not appropriately assess and address risk in its Mississippi Division pipeline system.

Ntsbnumber: PLD24FR003

Report Number: PIR-26-01

Addressee Name: ATMOS Energy Corporation

Addressee Status: Open - Initial Response Received

Addressee Organization Type: P-Private Industry

Communication Date: 2026-03-26

Communication Type: Transmittal Letter

Communication Contents: The National Transportation Safety Board (NTSB) is an independent federal agency charged by Congress with investigating every civil aviation accident in the United States and significant accidents in other modes of transportation—railroad, highway, marine, and pipeline. We determine the probable cause of the accidents and issue safety recommendations aimed at preventing future accidents. In addition, we carry out special studies concerning transportation safety and coordinate the resources of the federal government and other organizations to assist victims and their family members affected by major transportation disasters. We are providing the following information to urge Atmos Energy Corporation to act on the safety recommendation in this letter because we believe your organization can help reduce the risk of future accidents. For more information about the NTSB and our recommendation process, please see the attached one-page summary. This letter also includes information about our March 12, 2026, report, Atmos Energy Corporation Natural Gas-Fueled Home Explosions and Fires, Jackson, Mississippi, January 24, 2024, and January 27, 2024, NTSB/PIR-26-01. The details of this accident investigation and the resulting safety recommendations may be found in the attached report, which can also be accessed at http://www.ntsb.gov. As a result of this investigation, we identified the following safety issues: • Compression coupling leaks that the natural gas distribution operator had identified and left unrepaired. • Insufficient leak management program, which did not determine appropriate monitoring timelines for leaks in adverse-soil conditions. • Ineffective public awareness program, which did not adequately educate the public or emergency response officials on how to respond to a suspected natural gas leak. • Inadequate distribution integrity management program, which did not appropriately assess and address risk in its pipeline system. • Absence of natural gas detection alarms in buildings, which left occupants vulnerable to the dangers of unrecognized gas leaks. Accordingly, the NTSB makes the following safety recommendations to Atmos Energy Corporation (additional information regarding this recommendation can be found in the noted section of the report): • Develop and implement a program to locate and replace all mechanical couplings and mechanical joints located in expansive soils that are not resistant to pipe pullout with couplings and joints developed specifically for those conditions. The program should establish and make public the project milestones and timeline. (P-26-3) (See section 2.2.) • Update your companywide leak management program procedures to require weekly monitoring of nonhazardous (grade 2 or grade 3) belowground leaks identified in locations with adverse-soil conditions (such as water-saturated soil, flooding, drought, frozen ground, or settlement). (P-26-4) (See section 2.3.) • After completing the action described in P-26-4, implement a training program to maintain employee and contractor proficiency on the updated procedures. (P-26-5) (See section 2.3.) • Develop and implement a program to provide more frequent training to emergency response officials in all the distribution areas that you serve, including training on how to respond to natural gas-leak calls, and monitor the program for effectiveness. (P-26-6) (See section 2.4.) • Require your technicians who identify but do not repair a belowground natural gas leak to immediately notify people near the unrepaired leak that (1) the hazard potential of a leak can change over time, and (2) they should evacuate and then call 9 1 1 and Atmos Energy Corporation every time they smell natural gas odorant. (P-26-7) (See section 2.4.) • Develop and implement a program to proactively identify and collect missing service-line information for all your operating divisions. The program should (1) identify one or more methods for gaining additional system data and (2) establish and make public the milestones and timeline for acquiring the unknown system data. (P-26-8) (See section 2.5.) • Transition from a relative-risk model to a probabilistic distribution integrity management risk model. (P-26-9) (See section 2.5.) • Develop and implement a program that makes natural gas alarms available to members of the public who reside in your distribution areas. (P-26-10) (See section 2.6.) The NTSB is vitally interested in these recommendations because they are designed to prevent accidents and save lives. We would appreciate a response within 90 days of the date of this letter, detailing the actions you have taken or intend to take to implement these recommendations. When replying, please refer to the safety recommendations by number (Safety Recommendation P-26-3 through -10). We encourage you to submit your response to ExecutiveSecretariat@ntsb.gov. If your reply, including attachments, exceeds 20 megabytes, please e mail us at the same address for instructions on how to send larger documents. Please do not submit both an electronic copy and a hard copy of the same response. All communications regarding safety recommendations are stored by the NTSB and viewable by the public. Please do not send privileged or confidential communications in response to this recommendation. Responses marked as confidential or privileged (or similar designations) will be considered nonresponsive. In the likely event that your organization uses auto generated and/or preformatted confidentiality statements on letterhead or outgoing e-mails, please include a statement in your letter indicating that the information can be publicly released. If you have concerns about this protocol, please contact us at ExecutiveSecretariat@ntsb.gov. From Pipeline Investigation Report PIR-26-01 “Atmos Energy Corporation Natural Gas Fueled Home Explosions and Fires Jackson, Mississippi January 24, 2024, and January 27, 2024” published on March 26, 2026: 2.4 Ineffective Public Awareness Program Public Awareness Program Effectiveness Affected Public Atmos’s public awareness program’s effectiveness scores indicated that about 62% of the affected public within Atmos distribution areas, including areas in Mississippi, knew that they should leave the area and then call 9-1-1 or the gas company during a suspected natural gas leak. About 37% of those surveyed were unaware of how to safely respond to a suspected natural gas leak. Footnote: As discussed in section 1.9.2, survey percentages are not complete (do not total 100%), likely because of rounding or incomplete responses. Atmos’s public awareness program communication plan required the operator to educate members of the affected public (customers and noncustomers) on safety topics that included how to respond to a suspected natural gas leak. Atmos’s plan required the operator to communicate to customers twice a year and noncustomers once a year through delivery channels such as bill inserts (for customers) and television (for customers and noncustomers). However, several people smelled natural gas odorant before the accidents occurred but were unaware of pipeline safety guidance to respond to the smell of natural gas odorant by evacuating and then immediately calling 9-1-1 or the gas company (Atmos in this case). According to NTSB and Mississippi Public Service Commission interviews, at least three people smelled natural gas odorant on Bristol Boulevard before the accident and were unaware of the need to immediately report it, and at least two people smelled natural gas odorant on Shalimar Drive before the accident and were unaware of the need to immediately report it. Thus, Atmos’s public awareness program was ineffective at educating the public. In addition to this investigation, several NTSB investigations in the last 15 years have determined that the natural gas distribution operator’s public awarene

Addressee Organization Type: P-Private Industry

Communication Date: 2026-06-24

Communication Type: Official Correspondence

Communication Contents: -From John McDill, Senior Vice President Utility Operations: Atmos Energy shares the objective of public safety communication with all stakeholders, including clear safety communication with the affected public and the 1,400 communities we are privileged to serve. Our public awareness program complies with regulatory requirements and is aligned with established safety practices. Atmos Energy maintains an established public awareness program that is designed to educate customers and the public on how to recognize and respond to natural gas odors, including when to leave the area and contact emergency services. We ask the public to call 911 and Atmos Energy’s 24-hour emergency line every time they suspect a leak or think they smell natural gas regardless of a known active leak in the area. When notified, Atmos Energy will send a trained and qualified technician to fully investigate the report. We educate our customers about gas safety messaging in numerous ways. Our monthly customer invoices cover a variety of safety messaging, including how to detect a gas leak, what to do if a leak is suspected (including calling 911 and Atmos Energy’s 24-hour toll-free emergency line) and the importance of safe digging. There are several ways we include these messages: printed on the bill as a graphic or message, a printed paper insert (for customers who receive their bill via postal mail), and graphics on the email (for customers who receive their bill via email). In addition, printed and email customer correspondence includes leak detection messaging. In May 2026, we sent the first annual Spring Safety email to customers who have an email address on file highlighting how to recognize and what to do if there is a natural gas leak and how to safely dig. In addition, all customers annually receive direct mail that contains a Natural Gas Safety Guide and a specific brochure advising customers what they should do if they smell natural gas. The brochure contains a scratch and sniff section designed to bring awareness to the distinguishing odor added to make natural gas detectable. This approach for our public awareness program provides consistent, system-wide messaging that is not tied to an individual leak or condition. The Atmos Energy Customer Contact Center also communicates gas safety information during calls made to the contact center. The introduction message that every caller hears provides instructions on what to do if they smell gas or suspect a leak. Every caller hears an introduction message that provides instructions on what to do if the caller smells gas or suspects a leak, and every caller has the option of using a direct transfer to our 24-hour Emergency Services dispatch center. Agents in the customer contact center are required to include safety messages throughout their conversations with customers, and they actively listen for any indication of a possible safety concern on every call. We also educate the general public, whether customers or not, about natural gas safety through a multi-channel safety awareness strategy including proactive public awareness campaigns, community events, social media, and continued relationships with regulators, city leaders, and first responders. In addition, our public website is another source for information about how to recognize a leak. Specifically, our safety messaging advises that if someone suspects a natural gas leak, they should leave the area immediately and from a safe distance call 911 and Atmos Energy's 24-hour toll-free emergency number. Atmos Energy’s annual media campaigns across its service areas increase public awareness of natural gas safety. These campaigns use a multi-channel strategy to reach audiences in identified locations and include a combination of billboards, print advertising, broadcast and connected television, and various digital platforms to ensure a broad and targeted message delivery. It is important to provide consistent communication to the public about how to recognize and respond to natural gas odors. To further enhance our public awareness program, we are implementing this year an additional channel of supplemental communication to residential non customers in the vicinity of our distribution system assets. This communication will be mailed annually to those non-customers, and it will provide information about what to do if they smell natural gas or suspect a natural gas leak. The content will also include a brochure with a scratch and sniff section designed to bring awareness about the distinguishing odor added to make natural gas detectible. Our enhanced supplemental public awareness messaging combined with our enhanced leak management program (enhanced system monitoring, accelerated leak re-evaluation, expedited repairs) as outlined in P-26-4 provides measurable safety improvements. We believe that these safety improvements satisfy the intent of this Recommendation and accordingly, we ask that the NTSB close this Recommendation as acceptable.