Without downplaying the human side of the disaster, there is also a financial impact for almost every Australian.

Despite the halving of its share price since the mining boom peak seven years ago, BHP is our fifth-biggest listed company, and is held by most mainstream super funds. BHP's woes, unfortunately, are also yours and mine.

The story of corporate catastrophes is that the ramifications drag on and the stock price may never fully recover. Often a disaster exposes other problems, either about management or growth prospects.

In BHP's case it's a global glut in the minerals it digs up as China, its biggest customer, slows.

On top of that, this year's demerger of South32, containing most of what it inherited from its merger with Billiton when it changed pedigree, has proved detrimental for both.

BHP's saving grace is that its shares pay better dividends than even the banks in terms of yield.

Lessons from past disasters

The most infamous catastrophe remains Union Carbide's poisonous gas leak in India which killed an estimated 15,000 in 1984. The company claimed sabotage but critics pointed to slack safety standards. Its share price plunged 20 per cent. This took two weeks, as things were slower back then. But it eventually recovered and beat the pre-disaster price 18 months later. This owed more to a raging bull market than anything the company did.

BP's oil spill in the Gulf of Mexico was bad enough but the way it handled the crisis was possibly even worse. The US Congress threw the book at the company with charges of negligence and cover-ups. The share price plunged 55 per cent and four years on has recovered only half that, though the slump in the oil price hasn't helped.

The previous record holder for a US oil spill was the Exxon Valdez disaster in 1989. This was blamed on poor safety standards and maintenance. Curiously, Exxon's share price hardly dipped and quickly recovered. But again it coincided with the start of the post-1987-crash bull market.

This suggests a weak market, either overall or for what the company produces, will exaggerate the impact of a disaster on the share price, while a good one forgives almost anything.

Remember Firestone tyres on Ford cars were blowing out so often it was clearly more than coincidence? Each company blamed the other for design faults. Finally Ford instituted a $3 billion recall of the tyres, but not before several deaths and countless injuries. Ford's share price slipped 20 per cent over several months and kept sliding. Three years later it was down 73 per cent. Today Ford is worth only half as much as it was before the recall.

Compare that with Toyota which, unprompted, recalled 6.5 million vehicles worldwide for several possible safety issues, none of which had eventuated. Its share price slipped 3 per cent only to shoot up 56 per cent over the next year. The lesson in being pro-active is obvious.

Volkswagen did the opposite – denying, incredibly, that faulty brakes on some models might be a safety issue. More recently it was caught cheating with its engine emission readings. Its shares have crashed 60 per cent in six months, and there are even fears for Germany's economy.

The best comeback story is Qantas, which scored a spectacular own goal by grounding its entire fleet over a union dispute which went to arbitration but cost $194 million and goodness knows how much brand damage – though as it turned out, perhaps not that much anyway.

In the four years before the grounding Qantas shares had slumped 75 per cent. There they stayed until late last year, when they started a 160 per cent climb, thanks to lower oil prices, the post-grounding cost cutting and the end of the carbon tax. But they're still $2.75 a share shy of their peak.

In BHP's favour, it revealed the disaster so promptly that I got word of it before I even knew something had happened.

Also, it's a joint venture with Vale, so there will be others to share the blame.

But the full cost of the disaster in compensation and lost production may not be known for years. Markets might tolerate accidents, incompetence, negligence and even fraud, but never uncertainty.

If there's any suggestion that BHP's profits will be hit to the point that its dividend will be cut, super funds will head for the exit.

As it is, mining stocks are out of favour big time, and without a big drop in the dollar that's not about to change.

Twitter: @moneypotts