What Caused San Bruno Gas Explosion?
Last week’s explosion of a 54-year-old, 76-centimetre (30-inch) diameter high-pressure natural gas pipeline in San Bruno, California, raises troubling questions about ageing US infrastructure. The explosion and subsequent fire, fuelled by leaking gas, destroyed many houses and killed at least four people, with more deaths suspected.
According to the San Francisco Chronicle, workers from Pacific Gas and Electric, which operated the line, needed 2 hours to stop the gas flow. Modern pipelines have automated valves that stop gas flow when sensors detect a pressure drop. But to shut off the old pipeline, workers had to retrieve keys and drive to two secured sites 1.5 to 2 kilometres from the fire, then manually crank valves shut.
Read the whole thing.
Our infrastructure needs attention.