In Australia, the mother of an Australian miner killed in the Pike River disaster has joined a union advertising campaign against the giant mining company BHP Billiton.
Joanne Ufer, whose son Josh Ufer was one of the 29 victims of the disaster, has appeared in an advertisement urging BHP not to undermine safety in its operations.
The ABC reports that more than 3000 members of a coalmining union have launched rolling stoppages at seven mines BHP owns jointly with Mitsubishi.
They are opposing a push by the company to appoint its own staff to union safety positions.
In the ad, Ms Ufer says she has been deeply shocked by evidence of management negligence.
She says mine safety is too important to be handed over just to management.