Gas pipeline explosions, like the kind that hit Lawrence, Massachusetts recently, have been an ongoing concern to safety advocates and politicians.
Senator Markey (D-MA) in particular has led a call to action to improve safety on pipelines through the Securing America’s Future Energy: Protecting our Infrastructure of Pipelines and Enhancing Safety (SAFE PIPES) Act.
Yet incidents like the Lawrence explosion have remained relatively rare and haven't grown with additional pipeline miles according to numbers from the Pipeline and Hazardous Materials Safety Administration (PHMSA) and the National Transportation Safety Board (NTSB).
Major accidents reported by the NTSB have actually decreased substantially starting in the early 2000s.
Instead, mechanical fitting failures are increasingly common in the last five years, more than doubling from 2011 to 2016.
A 2016 report from PHMSA indicated that the majority of these incidents came from parts installed from 1960-1990. Most were steel parts but plastic pieces had the shortest lifespan. Most had equipment failures, as opposed to corrosion or welding issues, often related to coupling.
States with the most occurrences included Texas, Maryland, Illinois, Pennsylvania, and Indiana.
But the report does not indicate a cause for the increased number of failures.
Data from the Bureau of Labor Statistics show that employment in natural gas distribution, including installation and repair, has actually declined by 27 percent since 1990, or approximately 42,000 employees.