Metal Workers Union spokesman Anders Ferbe said, "It is completely unacceptable that there are such shortcomings in the working environment that people die on the job," TheLocal.se reported Friday.
Two men in their 60s performing routine maintenance at the SSAB coke plant in northern Sweden died Thursday when tar spilled out of a cistern, trapping them in an enclosure.
Both men were subcontractors whom SSAB said had performed the tasks before.
Ferbe questioned SSAB's reliance on subcontractors, alluding to a 2011 accident at another SSAB plant in which one person died and seven workers were burned when 40 tons of lime fell out of an oven.
Ferbe blamed the conservative government for what he said was reduced attention to workplace safety over the past seven years.
An SSAB manager, Per Bondemark, said there was no link between the work status of the two subcontractors and the accident. He said the same safety procedures were used by the company's employees.
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