Even before it opened in September 1991, the Westray underground coal mine near Stellerton, N.S., had been labelled by critics as a potential killer.

And on May 9, 1992, a blue-grey flash lit the pre-dawn sky as a methane-fueled fireball surged through the mine and triggered a coal dust explosion that shook houses a kilometre away, CBC News recorded.

The blast killed all 26 men who were working underground. Eleven bodies were never recovered.

Miner Vern Theriault, who joined the five-day search for survivors and to recover bodies, remembers the vain rescue attempt very well.

"I know what hell looks like after that," he said Tuesday at a news conference on the eve of the anniversary, according to CBC News.

In the weeks before it opened, Nova Scotia Liberal MLA Bernie Boudreau wrote to Labour Minister Leroy Legere warning the mine was "potentially one of the most dangerous in the world."

But the mine was welcomed for providing 300 badly needed jobs, despite the deadly record of local mines, where 246 workers had died in similar methane and coal-dust blasts up to 1950. Many originated in the same Foord coal seam that Westray would mine.

The inquiry into the disaster, which took five years, uncovered a fatal mix of corporate greed by mine-manager Curragh Resources Inc. of Toronto, bureaucratic bungling and government incompetence.

The report's title, as CBC noted, said it all: The Westray Story: A predictable Path to Disaster.

Most of the blame fell on Curragh and on government mine inspectors who overlooked flagrant safety violations.

Among the problems were a ventilation system ill equipped to keep methane and coal dust from building to dangerous levels, methane detectors that were disconnected because they went off so frequently, a mine layout that sacrificed safety for productivity and infrequent use of "stone-dusting" to neutralize the coal dust explosion threat.

The inquiry also found an "appalling lack of safety training and indoctrination" among the miners.

The objective, the report found, was to get the coal out and sold as quickly as possible.

"Since there was no discernible safety ethic, including a training program and a management safety mentality, there could be no continuum of responsible safety practice within that workplace," the report said, according to CBC.

"Complacency seemed to be the prevailing attitude at Westray — which at times regressed to a heedless disregard for the most fundamental safety imperatives."

After the blast, the mine was shut down. The surviving 117 members of the workforce received 12 weeks of severance pay, about $1.2 million, CBC reported.

The dead miners' families tried to sue the Nova Scotia government but the province's Supreme Court ruled the government was immune from lawsuits.

Curragh faced 52 non-criminal counts of operating an unsafe mine but went bankrupt in 1993. The charges were tossed out by the courts and criminal charges against two mine managers were stayed by the Crown, which said there was not enough evidence to guarantee a conviction.

Curragh founder Clifford Frame and former Westray president Clifford Frame boycotted the inquiry, staying in Toronto to avoid Nova Scotia subpoenas unenforceable outside the province.

The disaster did result in the federal Westray Act of 2004, which set down new rules for assessing criminal liability against corporations and their officials when workers are killed or injured on the job.

But Ramsey Hart of Mining Watch Canada told CBC this hasn't changed attitudes in the industry.

"Unfortunately, we are still seeing an unacceptable number of fatalities in mines," he said. "There are some disturbing indications that we may be losing some ground."

To mark the 20th anniversary, the United Mine Workers, supported by Defence Minister Peter MacKay, a Nova Scotia prosecutor at the time, Labour Minister Lisa Raitt and Nova Scotia New Democrat MP Robert Chisholm, is launching a campaign to raise awareness of the Westray Act.

"The bill got passed in 2004 ... over the years, I didn't see it being used," Theriault said. "There's charges but it's not being enforced. Let's use it."

Steelworkers Union national direct Ken Neumann noted only six charges have ever been laid and all were either settled through plea bargains or fines.

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