The National Transportation Safety Board has opened an investigation into the cause of an April gas explosion in northern Colorado that killed two men who were working on a water heater in a basement and badly injured a third person in the home.
“We are looking at the accident purely from a safety perspective,” NTSB spokesman Keith Holloway told ENR. “It’s too early to determine a cause, but we want to find whether this is an isolated incident or it could have national impact.” The NTSB investigates pipelines because they carry materials.