June 9, 1994
NTSB Number PAR-96/01
NTIS Number PB96-916501
On June 9, 1994, a 2-inch-diameter steel gas service line that had been exposed during excavation separated at a compression coupling about 5 feet from the wall of a retirement home in Allentown, Pennsylvania. The escaping gas flowed underground, passed through openings in the building foundation, migrated to other floors, and exploded. The accident resulted in 1 fatality, 66 injuries, and more than $5 million in property damage.
In its investigation of this accident, the Safety Board identified safety issues relating to pipeline excavation damage prevention and rapid shutdown of failed gas service lines.
As a result of its accident investigation, the National Transportation Safety Board issued safety recommendations to the Research and Special Programs Administration, the States and the District of Columbia, UGI Utilities, Inc., Environmental Preservation Associates, Inc., the Governor of the Commonwealth of Pennsylvania, the city of Allentown, the International Association of Fire Chiefs, the Department of Housing and Urban Development, the Allentown Housing Authority, the Associated General Contractors, and the National Utility Contractors Association.