"It is completely unacceptable that there are such shortcomings in the working environment that people die on the job," IF Metall spokesman Anders Ferbe told the TT news agency on Friday.
Two men in their sixties lost their lives when tar spilled out of a cistern, trapping them in the moat-like safety enclosure. They were carrying out routine maintenance when the accident occurred at the coke plant owned by SSAB. The men, who, SSAB were quick to underline, were subcontractors not employees, had performed the maintenance procedures before.
"Yet again, we have an accident involving subcontractors," Farbe said, adding that SSAB's reliance on third-party labour had to be questioned.
The tar would have had a temperature of around 30 to 40 degrees Celsius when it spilled out of the cistern. Swedish rescue services recovered the men's bodies a few hours later, as the response team had to build a new barricade and drain the tar before moving in.
In 2011, seven workers were burned when 40 tonnes of lime fell out of an oven at SSAB's Nordkalk plant in Luleå. A 23-year-old man died from the hot fumes. Pictures of one his badly scarred colleagues, who had 55 percent burns, made their way into the Swedish press after the accident two years ago.
The metal workers union said it had observed deteriorating focus on workplace safety in the past years under the conservative government.
"Unfortunately we can now see the effects of society's and the state's involvement in work place questions having decreased in the past seven years," Ferbe said.
At SSAB, however, Luleå area manager Per Bondemark said there was no link between the two victims' employment status and the accident. He said they would have observed exactly the same safety procedures had they been the company's own employees.
Sweden's new Labour Minister Elisabeth Svantesson has decided to sit on the fence in the meantime, and warned against coming to premature conclusions.
"We have to let the relevant authorities examined what has happened," she told TT via SMS.
The Swedish police has not taken over the investigation in conjunction with the Work Environment Authority (Arbetsmiljöverket).
SSAB underscored that the accident was "deeply tragic".
"Our thoughts are first and foremost with their relatives, friends and colleagues," said SSAB spokeswoman Maria Långberg.
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