Transport Canada won’t say what the minimum requirements are for making sure a parked train won’t roll away and it won’t disclose the rules set by the rail companies for keeping unattended trains with potentially dangerous goods stationary.

The CBC asked Transport Canada to clarify the rules for tying down a train a few days after the Lac Megantic tragedy. More than two days later, the response ignored the specific request for minimum requirements and referred to the Canadian Rail Operating Rules.

The guidelines in the CROR, however, lack specificity on parking trains.

Section 112, on "Securing Equipment", says: "When equipment is left at any point a sufficient number of hand brakes must be applied to prevent it from moving. Special instructions will indicate the minimum hand brake requirements for all locations where equipment is left."

The section goes on to discuss parking a train on a siding, and to specify that hand brakes need to be fully tested before they can be used to secure equipment.

Eight days after the initial request, Transport Canada continues to rebuff CBC's inquiries with vague answers.

"The rules provide specific instructions for the use of hand brakes to prevent the train from moving when equipment is not in use," it said in an email to CBC.

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"Each railway has instructions that further specify how many handbrakes are applied. These instructions also govern special circumstances such as a grade. The handbrake requirements are not load specific. Requirements are determined by the amount of cars, terrain, etc."

NDP MP Olivia Chow said that's not good enough.

"Canadians need to know that the trains coming through their neighbourhoods are safe," Chow said on Thursday.

That's why the Conservatives should not hide the operations of these trains, said Chow, vice chair of the House of Commons transport committee.

Chow and three other transport committee members have signed a letter requesting a special public committee meeting to examine what can be done to make sure past rail safety recommendations from both the TSB and the auditor general are implemented.

"We’re not tackling the precise cause of

[the] Lac-Mégantic tragedy. We'll wait for that," Chow said.

"But what we do know is that Transportation Safety Board’s previous recommendations on various derailments and how to prevent future derailments have not been implemented completely," Chow told CBC News.

With the four signatures, the committee is now required to hold a session to determine whether a broader public meeting should be convened.

"If there's nothing to hide, come clean. Tell Canadians what the operations are and whether they are safe or not."

Lac-Mégantic

In the early morning of July 6 a Montreal, Maine and Atlantic train, which included five engines, a boxcar and 72 cars of crude oil, left its parking spot in Nantes, Que., near the Maine border, and rumbled downhill into Lac-Mégantic. The crude oil cars separated from the engines and boxcar, and two explosions and a fire engulfed the town of 6,000.

Rescue officials have recovered 42 bodies and at least eight people are still believed missing.

The causes of the explosions are still a mystery, but what has consumed rail experts is what precautions did MMA locomotive engineer Tom Harding take to secure the train. Did he comply with MMA's own internal special instructions for that stretch of rail? Did the MMA guidelines meet the requirements of Transport Canada?

The company originally said after the accident that Harding had put on the air brakes and left the engine running when he jumped in a taxi to go to a hotel for the night. It also said that Harding applied the appropriate number of hand brakes. A fire started in the main engine, and the firefighters who extinguished the fire were accused of shutting down the engine, which released the brakes.

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A fire burned for nearly 24 hours after a train derailment in downtown Lac-Mégantic, Que., on July 6 after a train operated by MMA railways came off the tracks, spilling crude oil and causing explosions in the town of 6000. 42 bodies have been recovered. (Paul Chiasson/Canadian Press)

Last Wednesday, MMA chairman Ed Burkhardt confused the debate by saying Harding "told us he applied 11 hand brakes and our general feeling is that now, that is not true."

That the CROR allows individual companies to set their own special instructions creates confusion, says Ian Naish, a consultant with 27 years in transportation safety.

"The rules that are applied by Transport Canada, Rule 112, says that sufficient number of hand brakes must be applied when you are stopping a train and leaving it for a bit," explained Naish. "Well how do you define that? Various railways have defined it different ways for various types of grades, or types of trains.

"The way the regulatory system has operated for the last 20 to 25 years is, basically, the railways are responsible to regulate themselves, and the federal government is the overseer, the watcher of the way they operate."

Canadian Pacific, which has traditionally had the strictest rules on securing trains because of the risks of having steeper  lines through the Canadian Rockies, sent out new general operating instructions to its employees last week in anticipation of stricter Transport Canada rules.

On Thursday morning, new Transport Minister Lisa Raitt said if there are going to be any new rules coming from Transport Canada, "I'll be the one announcing them. As for Canadian Pacific, I'm very pleased to see they're taking a look at theirs and I spoke to CN this week and they’re doing the same."

Company rules on 'braking, securement' kept secret

The Montreal, Maine and Atlantic, CN and CP have refused to share their special instructions with the CBC, calling them proprietary, and Transport Canada said they can’t release it because "this type of information is not in the public domain, as it involves a third-party."

But an investigator with the Transportation Safety Board, which has looked at a long list of runaway trains, derailments and crashes, told the CBC that the rules are "vague and unclear."

The investigator, who spoke on condition of anonymity, cited the 13 CN coal cars that slid downhill last year in Hanlon, Alta., crashing into a parked train.

The TSB concluded the rules were unclear, CN's standards were inadequate and the staff had problems calculating just how many cars need to be locked down by hand.

Chow argues that Transport Canada has ignored too many recommendations, not only from the Transportation Safety Board but also a scathing report by the Auditor General in 2011 which says alarm bells were raised in 2005 about transporting dangerous goods.

"Transport Canada said it would take a year or two to implement the auditor general's recommendations, but these are not new problems," said Chow.

"It's been eight years that they had no comprehensive list of what's being transported, what's the performance standard and what's the quality assurance program" for transporting dangerous goods.

"That’s not acceptable."

The answer, says Chow, is not a public inquiry, but transparency and strong government.

"Without transparency we don't know who is accountable," she told CBC Thursday. "Why do we need a government if they don't regulate?"