7 March 2006
Fewer Humans, But More Error
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Train derailments are a serious problem in Canada. The Star has
investigated and mapped derailments from west to east coast as part of a probe into the 11,100 accidents ( from serious derailments to
crossing fatalities to more minor accidents ) on Canadian railways in the past decade.
This interactive map shows 350 main-track derailments over the past two years - where they occurred, what happened and
whether toxic substances were spilled. About 20 percent of these derailments involve trains transporting dangerous goods. Only about
5 percent of these serious accidents have prompted investigations from the Transportation Safety Board.
Map: 41 derailments involving dangerous goods.
Map: All 350 main-track derailments over the past two years.
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Clues to how railway safety has gone off the tracks can be found in Transportation Safety Board
reports, which have documented the problems that have arisen as the railway companies gained rule-making powers from the
government, laid off staff and increased their reliance on technology.
In 2001, both Canadian National Railway and Canadian Pacific Railway requested and received an exemption from some visual
"pull-by" inspections. Both companies had laid off staff - up to 50 percent each in some departments - in the
1990s, but they have invested heavily in technology designed in many ways to do a better job in checking rail. Mobile X-ray
machines can spot faults and cracks. Another machine checks for rail geometry.
And "wayside inspection stations" check for broken wheels and overheating axle bearings as trains pass, automatically sending
warnings to train crews and traffic control centres.
Because of technology, the companies say that when crews change on trains, the departing crew no longer needs to give the train the
once-over as the train slowly pulls away. (Pull-by inspections are still done for trains with dangerous goods
or loads that can easily shift.)
"We were holding the outbound crew waiting for departure," says Jim Kienzler, CP's director of regulatory affairs. "It
was delaying train times. We're running near capacity on our tracks. Any time we can take out of our system improves our capacity. And
we were finding nothing (using pull-bys)."
But on 12 Nov 2004, 10 CN multi-platform container cars derailed near Levis, Que. It was caused by a cracked
wheel, and could have been avoided had the practice of pull-by inspections not been abandoned, the TSB says in its report.
"If a pull-by inspection had been done when the crews changed, the condition of the wheel might have been
noticed," the TSB wrote of the Levis case.
The companies' logic? Automation and technology are supposed to give engineers the heads-up when there's a problem. That's
fine when computers and humans meet as they're supposed to, but disastrous when they don't.
That's exactly what happened on 21 Feb 2003, when the engineer and conductor of a CP Rail train ignored the warning signs -
and disobeyed safety procedures - resulting in an explosive derailment in the early morning near Melrose, Ont., east of Belleville.
Seven of the 21 derailed cars contained liquefied petroleum and exploded when they hit a locomotive waiting in a siding. The fire
burned for three days.
The train was also carrying anhydrous ammonia, a toxic, corrosive gas that can be fatal if inhaled, ingested, or absorbed through skin.
About 300 residents of Melrose were evacuated. Two crew members from the waiting train suffered burns from the fireballs of the
punctured tank cars.
The TSB concluded the train derailed because of an overheated axle. A "hot box detector" had indeed detected the overheating
axle, and an automated warning was sent to the crew.
"Any time we can take out of our system improves our capacity."
Jim Kienzler, CP's director of regulatory affairs, on the reason for ending some visual inspections.
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Standard operating procedures called for the crew to slow the train down and take it to the safest place where a visual inspection
could be conducted. Instead, the crew sped the train up because, at a siding a few kilometres away, another train was waiting for this
one to pass.
"This increased speed contributed to an increase in the number of cars involved in the derailment. Had the train slowed when the
first alarm tone was received, the extent of damage and the seriousness of the accident likely would have been reduced," said the
TSB.
In its ensuing investigation, the TSB noted that the automated alarm was sent, but that's all it was - a warning with no context. The
train had to completely pass over the hotbox detector before the engineer knew via computer specifically what the problem was.
The railways changed that. After this accident, the warning outlining the specific problem is sent immediately to the crew.
That highlights another problem: Automated audible messages won't work unless the crew is awake and paying attention to those
alerts. Such was the problem with another derailment later that year.
On 19 Oct 2003, a CP freight train eastbound for Toronto derailed at 11:18 p.m. because of a burned roller bearing. The
automated system worked as it should and had sent a message to the crew about the roller bearing.
But the crew wasn't listening. Their receiver was tuned to the wrong channel. The TSB suggested fatigue may have contributed to the
accident, saying the crew had little or no sleep in the past 24 hours.
A locomotive engineer or conductor may work up to 18 hours in a day - four more than a pilot, three more than a truck driver - and get
less mandated time off, the TSB noted.
In this case, the engineer had got off one train at 5:30 p.m. and was called back to work at 9:10, taking over a train that would derail
two hours later.
So why are crews rushed back into service? There are fewer of them, and there's more work in the booming business. Maintenance crews,
too, have been cut, a situation that may have led to a derailment on 21 May 2003, when a Canadian National train en route
to Toronto went off the tracks in the village of Gamebridge, Ont. About 250 tonnes of sulphuric acid was released and 50 people had to
be evacuated.
The TSB says the train derailed because the track was in a state of disrepair. The report points out that before 2002, it was the job of
four workers to inspect track over a 116-kilometre tract between North Bay and Washago. But after 2002, it became the job
of two people, who also had other inspection and maintenance duties on sidings and back tracks.
And inspectors no longer walk the track, but drive it, looking for faults. It had been checked visually just two days before the
derailment.
"The track defects could have been more readily detected if the inspector had checked on foot," the TSB wrote. "The level
of attention devoted to inspections in the area was not enough to identify the gradual deterioration of track condition."
But the TSB didn't blame the inspectors. It's harshest words were for CN, which ignored protocol after a test car inspected and found
11 "urgent" defects and 27 "near urgent defects" in the track in April. Protocol would have slowed down trains
through that area until an up-close visual inspection was complete and repairs made.
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