On February 22, 2025, about 10:05 a.m. local time, an explosion and subsequent fire resulted in the destruction of the Steffens Auto Parts commercial building in Hutchinson, Kansas. Subsequent investigation identified a leak in a natural gas pipeline owned and operated by ONE Gas, Inc. (which performed some of its functions through its Kansas Gas Service Division). The leak led to the evacuation of about 16 businesses and 51 residences. There were no injuries or fatalities.
We determined that the probable cause of the commercial building explosion in Hutchinson, Kansas, was the failure of a ONE Gas, Inc. (Kansas Gas Service) 1936-vintage 10-inch-diameter natural gas main at an oxy-acetylene girth weld that exhibited lack of penetration and fusion from original construction that decreased the strength of the weld; the weld failed when undetermined external forces induced an overstress fracture, allowing natural gas to migrate underground and accumulate within a commercial building, where it ignited.
According to pipeline industry guidance, vintage oxy-acetylene welds are at increased risk of failure under external forces, such as ones that produce earth movement. In this accident, a vintage oxy-acetylene weld failed without any indication of external forces. Careful monitoring of all external loading conditions can help identify areas where oxy-acetylene welds may have an increased risk of failure. Following the accident, ONE Gas implemented several safety actions designed to improve future safety performance. To better evaluate system integrity for all possible external forces, ONE Gas enhanced data collection practices, including review of utility crossings near vintage welds, to reduce the risk of damage to pipe welds. Additionally, ONE Gas developed a new field material failure report allowing failure data reporting in real time, improving data quality and timeliness for integrity management analysis.
This accident also underscores the value of natural gas alarms in buildings located near natural gas assets. Natural gas alarms provide both early warnings of dangerous gas concentrations and are a last line of defense when a leak investigation fails to identify a hazard. Further information about natural gas alarms is available on the NTSB website.
