Tag Archives: Vapor pressure

New York AG calls on PHMSA to close crude-by-rail safety loophole

Repost from Progressive Railroading
[Editor:  See also New York Wants Oil Companies to Treat Oil Shipped on Trains – Wall Street Journal, and NYS attorney general pushes federal limit on crude oil train explosion risk – Albany Times Union.  – RS]

New York AG calls on PHMSA to close crude-by-rail safety loophole

December 4, 2015

New York Attorney General Eric Schneiderman has called on the U.S. Pipeline and Hazardous Materials Safety Administration (PHMSA) to limit the vapor pressure of crude oil shipped by rail.

In a petition for rulemaking, Schneiderman asked the agency to require all crude transported by rail in the United States to achieve a vapor pressure of less than 9 pounds per square inch (psi). Vapor pressure is a key driver of the oil’s explosiveness and flammability, according to a press release issued by Schneiderman’s office.

In his petition, the attorney general argues that reducing crude oil vapor pressures is practical and necessary for minimizing the risk and severity of accidents involving tank cars.

Crude oils with the highest vapor pressures — including crude produced from the Bakken Shale formations in North Dakota — have the highest concentrations of propane, butane, ethane and other highly volatile gases, Schneiderman noted. 

While the vapor pressure of crude involved in train accidents is often undisclosed, the vapor pressure in such accidents in which the levels were disclosed have exceeded 9 psi, including the crude train accident in Lac Megantic, Quebec, that caused 47 fatalities.

“Recent catastrophic rail accidents send a clear warning that we need to do whatever we can to reduce the dangers that crude oil shipments pose to communities across New York State,” Schneiderman said in a prepared statement. “In New York, trains carrying millions of gallons of crude oil routinely travel through our cities and towns without any limit on its explosiveness or flammability — which makes crude oil more likely to catch fire and explode in train accidents. … The federal government needs to close this extremely dangerous loophole, and ensure that residents of the communities in harm’s way of oil trains receive the greatest possible protection.”