(The Canadian Press circulated the following story by Terri Theodore on August 25, 2010.)
VANCOUVER, B.C. — There are thousands of rail cars loaded with dangerous goods travelling North America carrying with them the potential for catastrophe because of a faulty part, a Transportation Safety Board report warns.
The problem came to light after a Canadian National Rail accident near Dugald, Manitoba, when the faulty part allowed a tank car loaded with more than 23,000 kilograms of flammable propylene to separate from the rest of the train.
What followed for safety board investigators was the unravelling of a puzzle and a strongly worded warning to Transport Canada, the rail industry, and its associations to keep an eye on the part.
On Jan. 14, 2009, a CN train was going just six kilometres an hour when the 41st car of the 72-car train detached. There was no derailment, no damage and no one was hurt.
The safety board’s Rob Johnston said it was to be a routine examination for their inspectors.
“It kind of surprised us. We went out there thinking that we would be looking at one car and when we started getting more information and through the course of the investigation, it became clear there was a much bigger problem here.”
An investigation found a defective stub sill — a part that helps joins cars together — and the same part is used in 41,000 other tank cars.
And while that particular design of stub sill is installed in just 13 per cent of the tank cars in North America, it accounts for 34 per cent of the broken stub sills across the continent. In Canada, every broken stub sill examined was one of that design.
“The potential is that at some time you may have a catastrophic failure of a tank car. These cars carry everything from chlorine to gasoline and everything in between,” Johnston said in an interview Wednesday after the report was released.
The broken part wasn’t a surprise to the several railways that carried the tank car after it was loaded with propylene in September 2008 in Indiana. The highly flammable liquid is a by-product of petroleum refining.
Workers with United Pacific Railroad in Illinois, the second railway to carry the car, did the first of two temporary welds on the stub sill and the car was prohibited from being placed in the middle of the train, with an order it must be transported as the rear car.
It was transported at the end of two subsequent CN trains before it reached Canada.
But the report said deficiencies in CN’s waybilling and car-tracking systems permitted the tank car to be placed on six different trains. It was switched 13 times and placed in the middle of trains seven times with the severely damaged and cracked stub sill.
Warren Chandler, CN Rail’s regional manager for public affairs, said while the rail cars aren’t specific to CN, after the incident the company reviewed its internal reporting procedures and put in place new processes to make sure it properly handles cars with defects.
“The issue here is properly designed equipment and proper reporting measures to ensure that issues are detected and when we do detect an issue, we want to make sure that it’s repaired or removed from service,” Chandler said.
Reporting the faulty parts is the key recommendation in the report.
“The Department of Transport, in conjunction with the railway industry and other North American regulators, (should) establish a protocol for reporting and analysing tank car stub sill failures so that unsafe cars are reported or removed from service,” the report stated.
In Canada, there’s no requirement to report cracked or broken stub sills in tank cars carrying dangerous goods and the TSB report said because not all bad parts are reported, the failure rate may be even higher.
In a statement, the Railway Association of Canada said Canada’s rail industry has rigid measures in place to make sure rail is the safest way to deliver dangerous goods and that 99.998 per cent of dangerous goods arrive safely by rail.
“Moreover, railway mechanical forces are trained to specifically look for stub sill defects during rail yard inspections at certified tank car facilities at regular intervals,” the statement said.
“Any defects or failures of the stub sill are reported immediately to the tank car owners and immediately taken out of service, and if a dangerous good is involved, it is also reported to Transport Canada.
Another concern for the TSB involves the growing length and weight of trains, which was raised in the board’s safety issues watchlist issued last March.
Johnston said the stub sills were manufactured in the 1990s for trains that are about half the length and weight of those currently running on Canadian rails now.
“That’s a big difference,” Johnston said. “Trains and car design criteria must evolve over time and keep pace with operational demands or accidents may happen. This is a major safety concern.”