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Bakken Crude, Bridge safety, Broken rail, Crude By Rail, Derailment, Environmental review, Explosion, Fire, High Hazard Flammable Trains (HHFTs), Hospitals, Oil spill, Risk Assessment, Schools, Tar sands crude, Train length, Train weight

Critics say oil train report underestimates risk

Repost from the Spokane Spokesman-Review
[Editor:  Oh…this sounds SO familiar….  Benicia sends solidarity and support to our friends in Washington state.  – RS]

Critics say oil trains report underestimates risk

By Becky Kramer, December 18, 2015
In this Oct. 1, 2014 file photo, train cars carrying flammable liquids heads west through downtown Spokane, Wash. | Dan Pelle photo

The chance of an oil train derailing and dumping its cargo between Spokane and a new terminal proposed for Vancouver, Washington, is extremely low, according to a risk assessment prepared for state officials.

Such a derailment would probably occur only once every 12 years, and in the most likely scenario, only half a tank car of oil would be spilled, according to the report.

But critics say the risk assessment – which includes work by three Texas consultants who are former BNSF Railway employees and count the railroad as a client – is based on generic accident data, and likely lowballs the risk of a fiery derailment in Spokane and other communities on the trains’ route.

The consultants didn’t use accident data from oil train wrecks when they calculated the low probability of a derailment and spill. The report says that shipping large amounts of oil by rail is such a recent phenomanon that there isn’t enough data to produce a statistically valid risk assessment. Instead, the consultants drew on decades of state and national data about train accidents.

That approach is problematic, said Fred Millar, an expert in hazardous materials shipments.

Probability research is “a shaky science” to begin with, said Millar, who is a consultant for Earthjustice, an environmental law firm opposed to the terminal. “The only way that you can get anything that’s even partly respectable in a quantitative risk assessment is if you have a full set of relevant data.”

To look at accident rates for freight trains, and assume you can draw credible comparisons for oil trains, is “very chancy,” he said. “Unit trains of crude oil are a much different animal…They’re very long and heavy, that makes them hard to handle. They come off the rails.”

And, they’re carrying highly flammable fuel, he said.

Terminal would bring four more oil trains through Spokane daily
The proposed Vancouver Energy terminal would be one of the largest in the nation, accepting about 360,000 barrels of crude oil daily from North Dakota’s Bakken oil fields and Alberta’s tar sands. For Spokane and Sandpoint, the terminal would mean four more 100-car oil trains rumbling through town each day – on top of the two or three per day that currently make the trip.

The proposed $210 million terminal is a joint venture between Tesoro Corp. and Savage Companies. Oil from rail cars would be unloaded at the terminal and barged down the Columbia River en route to West Coast refineries.

A spill risk assessment was part of the project’s draft environmental impact statement, which was released late last month. A public meeting on the draft EIS takes place Jan. 14 in Spokane Valley. State officials are accepting public comments on the document through Jan. 22.

The spill risk work was done by a New York company – Environmental Research Consulting – and MainLine Management of Texas, whose three employees are former BNSF employees, and whose website lists BNSF Railway as a client. The company has also done work for the Port of Vancouver, where the terminal would be located.

The risk analysis assumes the trains would make a 1,000-mile loop through the state. From Spokane, the mile-long oil trains would head south, following the Columbia River to Vancouver. After the trains unloaded the oil, they would head north, crossing the Cascade Range at Stampede Pass before returning through Spokane with empty cars.

Report used data on hazardous materials spills

Oil train derailments have been responsible for a string of fiery explosions across North America in the past three years – including a 2013 accident that killed 47 people in the small town of Lac-Megantic, Quebec. Other oil train derailments have led to evacuations, oil spills into waterways and fires that burned for days.

But since shipping crude oil by train is relatively new, there’s not enough statistical information about oil train accidents to do risk calculations, the consultants said several times in the risk assessment.

Instead, they looked at federal and state data on train derailments and spills of hazardous materials dating back to 1975, determining that the extra oil train traffic between Spokane and Vancouver posed little risk to communities.

Dagmar Schmidt Etkin, president of Environmental Research Consulting, declined to answer questions about the risk assessment. Calls to MainLine Management, which is working under Schmidt Etkin, were not returned.

Stephen Posner, manager for the state’s Energy Facilities Siting Council, which is overseeing the preparation of the environmental impact statement, dismissed questions about potential conflicts of interest.

“There aren’t a lot of people who have the expertise to do this type of analysis,” Posner said.

Schmidt Etkin also worked on a 2014 oil train report to the Washington Legislature, he said. “She’s highly regarded in the field.”

According to her company website, Schmidt Etkin has a doctorate from Harvard in evolutionary biology. The site says she provides spill and risk analysis to government regulators, nonprofits and industry groups. Her client list includes the U.S. Environmental Protection Agency, the Coast Guard and the American Petroleum Institute.

Posner reviewed the scope of work outlined for the spill risk analysis.

“We put together the best analysis we could with limited sources of information,” he said. “This is a draft document. We’re looking for input from the public on how we can make it better.”

Spokane ‘a more perilous situation’

The “worst case” scenario developed for the risk assessment has also drawn criticism. The consultants based it on an oil train losing 20,000 barrels of oil during a derailment. The risk assessment indicates that would be an improbable event, occurring only once every 12,000 to 22,000 years.

In fact, twice as much crude oil was released during the 2013 Lac-Megantic accident in Quebec, said Matt Krogh, who works for Forest Ethics in Bellingham, Washington, which also opposes construction of the Vancouver Energy Terminal.

“If I was looking at this as a state regulator, and I saw this was wrong – quite wrong – I would have them go back to the drawing board for all of it,” Krogh said.

Krogh said he’s disappointed that former BNSF employees didn’t use their expertise to provide a more meaningful risk analysis. Instead of looking at national data, they could have addressed specific risks in the Northwest, he said.

Oil trains roll through downtown Spokane on elevated bridges, in close proximity to schools, hospitals, apartments and work places. In recent years, the bridges have seen an increase in both coal and oil train traffic, Krogh said.

“The No. 1 cause of derailments is broken tracks, and the No. 1 cause of broken tracks is axle weight,” he said. “We can talk about national figures, but when you talk about Spokane as a rail funnel for the Northwest, you have a more perilous situation based on the large number of heavy trains.”

Elevated rail bridges pose an added risk for communities, said Millar, the Earthjustice consultant. The Lac-Megantic accident was so deadly because the unmanned train sped downhill and tank cars crashed into each other, he said. Not all of the cars were punctured in the crash, but once the oil started burning, the fire spread, he said.

“If you have elevated tracks and the cars start falling off the tracks, they’re piling on top of each other,” Millar said. “That’s what Spokane has to worry about – the cars setting each other off.”

Governor has the final say

Railroad industry officials say that 99.9 percent of trains carrying hazardous materials reach their destination without releases. According to the risk assessment, BNSF had only three reported train derailments per year in 2011, 2012 and 2013. The railroad has spent millions of dollars upgrading tracks in Washington in recent years, and the tracks get inspected regularly, according to company officials.

Whether the Vancouver Energy Terminal is built is ultimately Gov. Jay Inslee’s decision. After the final environment impact statement is released, the 10-member Energy and Facilities Siting Council will make a recommendation to the governor, who has the final say.

Environmental impact statements lay out the risks of projects, allowing regulators to seek mitigation. So, it’s important that the EIS is accurate, said Krogh, of Forest Ethics.

In Kern County, California, Earthjustice is suing over the environmental impact statement prepared for an oil refinery expansion. According to the lawsuit, the EIS failed to adequately address the risk to communities from increased oil train traffic.

“If you have a risk that’s grossly underestimated, you’ll be making public policy decisions based on flawed data,” Krogh said.

Bakken Crude, Ban oil trains, Bomb Trains, CPC-1232, Crude By Rail, Derailment, Explosion, Federal Regulation (U.S.), Fire, Hazmat notification, Keep it in the ground, Rail infrastructure, Spill prevention and response, Tank car design, Tank car retirement, Tank car retrofit, Tar sands crude, Train length, Train speed, Train weight

New Oil Train Safety Regs Focus on Accident Response, Not Prevention

Repost from Center for Biological Diversity

CenterForBiolDiv_logoNew Oil Train Safety Regs Focus on Accident Response, Not Prevention

Long Phase-out of Hazardous Cars, Inadequate Speed Limits Leave Communities at Risk of Explosive Derailments

For Immediate Release, December 7, 2015
Contact: Jared Margolis, (802) 310-4054

WASHINGTON— A new transportation bill signed by President Obama includes provisions intended to improve the safety of oil trains, but leaves puncture-prone tank cars in service for years and fails to address the speed, length and weight of trains that experts point to as the leading causes of explosive derailments. The bill upgrades safety features on oil train tank cars and requires railroads to provide emergency responders with real-time information about when and where dangerous oil cargoes are being transported but doesn’t do enough to prevent oil train accidents, which have risen sharply in recent years.

“While these regulations improve our ability to prepare for oil train disasters they do virtually nothing to prevent them from ever occurring in the first place,” said Jared Margolis, an attorney with the Center for Biological Diversity who focuses on the impacts of energy development on endangered species. “Until we dramatically reduce the speed and length of these bomb trains it’s only a matter of time before the next explosive derailment sends fireballs rolling through one of our communities.”

The new regulations will require all oil train tank cars to include fire-resistant ceramic coatings and protections for protruding top fittings. The final rule issued by federal regulators in May only required oil trains with 35 loaded oil tank cars or 20-car blocks of oil tank cars to implement the new standards, and would not have required the ceramic blankets or top fitting protections for all retrofitted cars.

But experts say even the protective measures included in the new transportation regulations signed into law on Friday will do little to prevent a spill if a train derails at speeds faster than 18 mph, and oil trains are permitted to travel at 40 mph to 50 mph. And the new regulations do not require the phase-out of dangerous puncture-prone tank cars to begin until 2018, and allows them to remain in service until 2029.

“It’s irresponsible to continue to allow these bomb trains to roll through the middle of our communities and across some our most pristine landscapes,” said Margolis. “We need to quit pretending we can make these dangerous trains safe and simply ban them altogether.”

Congress has directed the U.S. Department of Transportation to continue requiring notifications to states of train routes and frequencies so communities can better prepare to respond to train derailments, explosions and oil spills. However, the new regulations do nothing to remedy the track infrastructure problems, or the excessive length and weight of oil trains, cited as leading causes of derailments. Further, it remains unclear whether the public will have access to information about these hazards.

“Keeping information on oil trains from public scrutiny is outrageous, and only serves to protect the corporate interests that care little about the risk to the homes, schools and wild areas that these trains threaten,” said Margolis. “We need to keep these trains off the tracks and keep these dangerous fossil fuels in the ground, rather than keeping the public in the dark.”

Background 

The National Transportation Safety Board has repeatedly found that current tank cars are prone to puncture on impact, spilling oil and often triggering destructive fires and explosions. But federal regulators have ignored the safety board’s official recommendation to stop shipping crude oil in the hazardous tank cars. Recent derailments and explosions have made clear that even the newer tank cars, known as CPC-1232s, are not significantly safer, often puncturing at low speeds.

The recent surge in U.S. and Canadian oil production, much of it from Bakken shale and Alberta tar sands, has led to a more than 4,000 percent increase in crude oil shipped by rail since 2005, primarily in trains with as many as 120 oil cars that are more than 1.5 miles long. The result has been oil spills, destructive fires, and explosions when oil trains have derailed. More oil spilled in train accidents just in 2013 than in the 38 years from 1975 to 2012 combined.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 900,000 members and online activists dedicated to the protection of endangered species and wild places.
Broken rail, Crude By Rail, Derailment, Ethanol, Federal Regulation (U.S.), High Hazard Flammable Trains (HHFTs), Rail industry lobby, Rail wear limits, Tank car retirement, Tank car retrofit, Track maintenance, Train speed, Train weight

AP: Railroads beat back new safety rules after derailments

Repost from the Boston Herald

AP: Railroads beat back new safety rules after derailments

By Matthew Brown and Michael Kunzelman, December 05, 2015
FILE -In this Monday, Feb. 23, 2015, file photo, clean up continues near Mount Carbon, W.Va., where a train derailed and sent a tanker with crude oil into the Kanawha River. A little-known truth about North American railroads: No rules govern when rail becomes too worn down. Since 2000, U.S. officials blamed rail wear as the direct cause of 111 derailments causing $11 million in damage. (AP Photo/Chris Tilley, File)

A pair of train derailments in 2012 that killed two people in Maryland and triggered a fiery explosion in Ohio exposed a little-known and unsettling truth about railroads in the U.S. and Canada: No rules govern when rail becomes too worn down to be used for hauling hazardous chemicals, thousands of tons of freight or myriad other products on almost 170,000 miles of track.

U.S. transportation officials moved to establish universal standards for when such steel gets replaced, but resistance from major freight railroads killed that bid, according to Associated Press interviews with U.S. and Canadian transportation officials, industry representatives and safety investigators.

Now, following yet another major accident linked to worn-out rails — 27 tanker cars carrying crude oil that derailed and exploded in West Virginia earlier this year — regulators are reviving the prospect of new rules for worn rails and vowing they won’t allow the industry to sideline their efforts.

“We try to look at absolutely every place where we can affect and improve safety,” said Federal Railroad Administrator Sarah Feinberg. “Track generally is the place that we’re focusing at the moment, and it’s clearly overdue. Rail head wear is one place in particular that we feel like needs to be addressed as soon as possible.”

An official announcement on the agency’s intentions to revisit rail wear is expected by the end of the year.

In the meantime, federal regulators haven’t taken the positive steps that they need to, said Ronald Goldman, an attorney for the families of the two 19-year-old women who died in a 2012 derailment outside Baltimore.

“It’s a lack of will, not a lack of ability, in my opinion,” he added.

Industry supporters argue that the seven major freight railroads in the U.S. and Canada are in the best position to know what is going on with their lines, including when they need to be replaced or have the maximum speeds for trains traveling on them lowered. They also note a long-term decline in accidents that has reduced the frequency of derailments by more than 40 percent since 2000.

All sides agree it’s difficult to pinpoint how many accidents are tied to worn rail. Since 2000, U.S. officials blamed rail wear as the direct cause of 111 derailments causing $11 million in damage.

That’s less than 1 percent of all accidents, yet it masks a broader safety dilemma: Years of massive loads rolling over a rail will exacerbate defects in the steel, such as cracks or fractures. Investigators ultimately list the defect as the cause of a derailment, but it might never have been a problem if the rail had not been worn down.

“Rail defects are internal and rail wear is external, and when external meets internal, that’s when problems may arise,” said John Zuspan of Track Guy Consultants, a Pennsylvania firm that offers track inspections, safety training and other services for railroads.

Two accident causes in particular have the strongest correlation with worn-out rails: “detail fractures” that result from fatigued metal, and “vertical splits” in the head of the rail, where it makes contact with a train’s wheels, according to the FRA.

Those problems caused a combined 1,200 derailments with $300 million in damages, three deaths and 29 people injured in the U.S. between 2000 and the present, according to accident records reviewed by the AP.

Among them was the July 2012 derailment of a Norfolk Southern Railway train hauling ethanol and other products through Columbus, Ohio. Seventeen cars derailed, including three hauling highly flammable ethanol that exploded into flames, triggering an evacuation of surrounding neighborhoods.

A month later, another accident occurred involving a CSX Transportation train hauling coal over a bridge along Main Street in Ellicott City, Maryland, outside Baltimore. Twenty-one cars derailed when the company’s worn-down rail split beneath the weight of the coal cars. The two college students sitting on the bridge died, crushed by thousands of pounds of spilled coal.

The victims’ families reached a settlement with CSX last year for undisclosed terms. Goldman, the families’ attorney, said he pressed federal officials for a forum that would allow his clients to testify about the issue, but “nothing really happened.”

A month after the CSX derailment, federal regulators asked the Rail Safety Advisory Committee — a panel created by the Railroad Administration to include the industry and others in fashioning safety rules — to craft new standards to reduce the risks of worn-down rail. The committee set up a 116-person working group to tackle the problem, made up of industry representatives, government officials, consultants, researchers and railroad worker unions.

The group included 55 representatives from the major freight railroads and their industry organization, the Association of American Railroads. The FRA had 14 seats at the table and their counterparts from Transport Canada had five.

Following several meetings in 2012 and 2013, the group — which required consensus before recommending action — agreed on voluntary guidance for companies to manage rail wear, but no new regulations.

“There was certainly a lot of pushback and a lot of political pressure put on FRA not to adopt regulations for rail wear,” said Richard Inclima, director of safety for the union that represents track inspectors and a member of the working group. “Rail wear limits were on the table. The industry raised a lot of arguments against rail wear limits.”

“The industry doesn’t want to be regulated,” he added. “That’s no secret.”

The railroads’ opposition was confirmed by others involved with the group’s work including from the National Transportation Safety Board, the FRA and Transport Canada.

Association of American Railroads spokesman Ed Greenberg said the railroads were “unaware of any science-based data supporting rail wear limits.”

NTSB investigator Richard Hipskind, who took part in the Ellicott City and Columbus accident investigations and later served on the rail wear working group, said more research would be needed to establish universal standards.

Railroads have their own internal standards for rail wear, and have replaced more than 30,000 miles of rail since 2010, according to reports submitted by the major railroads to the U.S Surface Transportation Board, a semiautonomous agency under the umbrella of the U.S. Department of Transportation.

Standards vary among railroads and are complicated by differences in how much weight a given line bears, whether it’s in a wet or dry climate, and if the line goes through mountains or involves lots of turns. Those variables can make the difference between well-worn rail that’s still safe and routes that poses a heightened safety hazard, according to industry experts and safety officials.

Greenberg said the industry takes an aggressive approach to identifying and removing defective or worn sections of rail.

“Each railroad has its distinct operating environment and operating conditions that would be factored into this,” Greenberg said. He added that the industry was now interested in “renewed dialogue” with the FRA on the topic.

The AP requested details on rail wear standards from each of the seven major freight railroads — BNSF Railway, Union Pacific, Canadian Pacific, CSX, Canadian National, Norfolk Southern and Kansas City Southern. They either refused the request or referred questions to the railroad association, which also declined to release the standards.

Public attention to train derailments increased sharply after July 2013, when an out-of-control oil train derailed and exploded in Lac-Megantic, Quebec, killing 47 people. One of the most significant changes to emerge from that and other accidents involving crude and ethanol was a mandate for companies to phase out or upgrade tens of thousands of tank cars that are prone to rupture.

Those are important changes, said James Horbay, a rail safety engineer with Transport Canada. But what causes trains to come off the tracks in the first place needs to be resolved, he said.

“If you crash an airplane, are you going to say, ‘Let’s build an airplane that’s not going to fall apart when it hits the ground?'” he asked. “Whether rail wear is something that should be looked at is a good question to ask. You’re going right to the cause now.”

Matthew Brown reported from Billings, Montana.  Michael Kunzelman reported from Baton Rouge, Louisiana. 
Crude By Rail, Derailment, Explosion, Fire, Massive increase in crude-by-rail, Rail infrastructure, Rail inspection, Rail Safety, Sloshing of oil, Tar sands crude, Train speed, Train weight, Wide gauge

MUST READ: Hauling crude oil may be causing train tracks to fail

Repost from the Los Angeles Times

Why are so many oil trains crashing? Track problems may be to blame

Ralph Vartabedian, October 7, 2015
Oil train derailment
Smoke and flames erupt from the scene of a train derailment March 5, 2015, near Galena, Ill. A BNSF Railway freight train loaded with crude oil derailed in a rural area where the Galena River meets the Mississippi. (Mike Burley / Associated Press)

The only sign of trouble aboard a Norfolk Southern train, hauling roughly 9,000 tons of Canadian crude in western Pennsylvania last year, was a moderate sway in the locomotive as it entered a bend on the Kiskiminetas River.

The first 66 cars had passed safely around the curve when the emergency brakes suddenly engaged, slamming the train to a stop. The conductor trudged back nearly a mile through newly fallen snow to see what happened.

Twenty-one cars had derailed, one slamming through the wall of a nearby factory. Four tank cars were punctured, sending 4,300 gallons of crude pouring out of the tangled wreckage.

Freight train derailment
Cars are seen from a freight train derailment on Feb. 13, 2014, in Vandergrift, Pa. (Darrell Sapp / Associated Press)

The cause of the accident in North Vandergrift was identified as a failure in the rails — not aging or poorly maintained tracks, but a relatively new section laid less than a year earlier.

The February 2014 crash fits into an alarming pattern across North America that helps explain the significant rise of derailments involving oil-hauling trains over the last three years, even as railroads are investing billions of dollars in improving the safety of their networks. A review of 31 crashes that have occurred on oil trains since 2013 puts track failure at the heart of the growing safety problem.

Track problems were blamed on 59% of the crashes, more than double the overall rate for freight train accidents, according to a Times analysis of accident reports. Investigators and rail safety experts are looking at how the weight and movements of oil trains may be causing higher than expected track failures.

The growing number of trains hauling crude oil from Canada and the Northern Plains are among the heaviest on the rails today, many extending more than 100 cars in length and weighing a cumulative 19,000 tons or more.

Not since the early days of John D. Rockefeller’s oil trust have railroads played such a central role in moving oil from wells to refineries. Oil shipments by rail have soared — an 18-fold increase between 2010 and 2014 — as domestic oil production has escalated faster than the construction of new pipelines to carry it to market.

Concerns about the safety of hauling crude began to rise after the horrific Lac-Megantic accident in Quebec in July 2013 that left 47 people dead and the city’s downtown in ruins.

The Federal Railroad Administration is preparing in coming weeks to issue a new set of initiatives to address the track problems, after previously clamping tighter restrictions on tank car designs and railroad operations. But solving the track problems could be a formidable challenge.

Oil train crashes since 2013
Infographic: Oil train crashes since 2013

Sarah Feinberg, chief of the Federal Railroad Administration, said the agency is working hard to improve safety, but preventing accidents that result from defective track involves finding a needle in every haystack along thousands of miles of track.

“We have been incredibly lucky that the accidents have happened mostly in rural areas,” she said. “Some of them have been very close calls.”

The crashes have occurred as the nation’s railroad system is being asked to do more than at any time in history, putting additional wear and tear on the tracks. Since 2001, railroads have seen a modest 12% increase in the number of cars they haul, but a 24% jump in the more comprehensive measurement of cargo that looks at the weight and train mileage the system has to bear, known as ton-miles, according to industry data.

Though railroads have significantly improved safety in general, the oil train accidents are a worrisome trend in the opposite direction and not fully understood.

Of the 31 crashes involving crude or ethanol since 2013, 17 were related to track problems and 12 a mix of other causes. The cause of the two other crashes remains unclear. The count is based on both final or preliminary government and railroad investigations that were collected by The Times under the Freedom of Information Act or in U.S., Canadian and railroad company filings.

About two-thirds of the accidents resulted in spills, fires or explosions, a record that has already prompted regulators to demand stronger tank cars and other safety measures.

Weight, oil sloshing and cold temperatures are among the issues that might be exacerbating the problem, according to rail safety experts.

Investigators at Safety Transportation Board Canada, which is investigating the eight accidents that have occurred in that country, are beginning to suspect that the oil trains are causing unusual track damage.

“Petroleum crude oil unit trains transporting heavily loaded tank cars will tend to impart higher than usual forces to the track infrastructure during their operation,” the safety board said in a report this year. “These higher forces expose any weaknesses that may be present in the track structure, making the track more susceptible to failure.”

Rick Inclima, safety director at the Brotherhood of Maintenance of Way Employees, also said that oil trains could be creating unique stresses on the track. “You can certainly get some rhythmic forces in … oil trains that you might not see on a mixed freight train with cars of different sizes, weights and commodities,” he said.

The nation’s major railroads are investing record amounts of money to upgrade their tracks and improve safety. The seven class-one railroads, which haul the majority of the nation’s freight, are spending $29 billion this year on their systems, nearly double the level of 2001, according to the American Assn. of Railroads. The trade group did not have any response to The Times analysis of oil train accidents, though it said its member companies exceed federal requirements for inspection and safety.

But that has not eliminated the problem. While all types of derailments dropped 17% over the last three years, there are still more than three every day across the nation, involving trains carrying a variety of freight, according to federal safety data. Bad track accounts for about 27% of overall accidents, less than half the rate that track problems are contributing to oil train accidents.

Though railroad technology may seem antiquated in a digital age, it relies on incredible precision to control monstrously heavy loads. The track in North Vandergrift, Pa., where the Norfolk Southern accident occurred, carries about 30 million tons of freight every year.

The relentless pounding plays havoc with any metallurgical flaw. Wooden ties deteriorate as they age. And other track components crack.

Investigators attributed the Pennsylvania derailment to a “wide gauge” failure, in which the rails were pushed too far apart to keep the wheels on the tracks.

The freight tracks in the U.S. and most of the world are supposed to be 56.5 inches apart, a width known as the gauge. Just three inches of movement can cause a derailment. And even if tracks conform to federal standards, they can separate under the force of a heavy train.

“Wide gauge” is the single largest cause of accidents involving track defects. In the case of the Pennsylvania derailment, it was broken spikes that caused the rail to widen, even though the track had been replaced in 2012, according to Federal Railroad Administration officials.

Private railroad experts have suggested that the sloshing of oil inside the cars may also be involved in the derailments.

Tank cars are only partially filled with oil, allowing for expansion if the temperature increases. The tanks have internal baffles, but the liquid can still slosh as the cars move, causing higher dynamic loads, said Bill Keppen, an independent rail safety expert. “Sloshing increases the stress on the track,” he said.

Federal safety experts said if sloshing does have an effect, they do not consider it significant.

The Times examination of accident reports also shows the large majority of derailments occurred in below freezing temperatures, ranging down to 23 below zero in a crash this year in Ontario.

As temperatures drop, steel rails progressively shrink, amplifying the potential for any existing defect to cause a failure, FRA safety experts said in interviews. Frozen ballast, the crushed rock that forms the rail bed, also causes rail to undergo greater shocks under the load of heavy trains.

Federal regulators and the industry are trying to improve safety, but opinions are sharply divided about exactly what measures are needed.

The Federal Railroad Administration, for example, has ordered that crude-carrying trains can travel at no more than 40 miles per hour in urban areas. But the North Vandergrift train was going only 36 mph. Nineteen of the trains whose speeds are known were moving 40 mph or slower, and no train was going faster than 50 mph, records show.

The railroad administration has increased its track inspections and railroads have agreed to increase their own inspections, according to Matthew Lehner, the agency’s communications director.

“In the coming weeks, the Federal Railroad Administration plans to announce additional steps to prevent crude oil train derailments,” Lehner said.

Critics say that many of the safety initiatives adopted so far reflect a policy aimed at mitigating the damage caused by derailments rather than preventing them.

“The attention has changed,” said Brigham McCown, former chief of the federal agency that sets tank car standards. “I hear people say, ‘It happens, they derail.’ I think that is an untenable position. As a safety regulator, I don’t think you can ever say, ‘Things blow up,’ or ‘Things crash.’ I believe the Department of Transportation has myopically focused on incident mitigation. Prevention should be the first question they should address.”