(Adds background on smelter closure, company spokesman's comments)
Nov 20 (Reuters) - Global miner Rio Tinto Plc restarted the smelter at its large Kennecott mine in the United States last Friday after a nearly six-week outage but force majeure on refined copper has not yet been lifted, a company spokesman said on Monday.
There was no timeline for when the force majeure would be lifted, spokesman Kyle Bennett said. A force majeure is usually implemented by companies during unforeseen events when they cannot meet commitments to customers.
Rio Tinto halted production of refined copper at its smelter at the Utah-based mine on Oct. 8 after a worker was exposed to sulfur dioxide gases at the plant while removing debris from a boiler. The worker died two days later.
Mining and milling operations had continued while the smelter was down, with ore being stockpiled for later processing, Bennett said.
"Everything's running normally," Bennett said via telephone, adding that the company had put in place a number of additional controls and offered more training after the incident.
Rio Tinto Kennecott comprises nearly 20 percent of U.S. copper production. The unit produced 156,500 tonnes of refined copper in 2016, about 63 percent of group output. (Reporting by Nicole Mordant in Vancouver; Editing by Sandra Maler and Matthew Lewis)