by Mike Hughlett, StarTribune (February 5, 2022) – “CO2 is a hazardous material that can lead to absolutely disastrous ruptures,” said Bill Caram, executive director of the Pipeline Safety Trust, a Washington state-based group. While CO2 isn’t explosive like natural gas, it’s an asphyxiant that can be fatal in large doses. CO2 flowing through pipelines is pressurized. It has the density of a liquid and the viscosity of gas — both good traits for transport. But in a rupture, CO2 rapidly depressurizes and returns to a pure gas phase, raising the risk of “ductile fractures,” said the Pipeline Safety Trust’s Caram. “If there is a ductile fracture, it can rip the line like a zipper and it can be miles long,” he said.