TORONTO (Reuters) - Rio Tinto (RIO.L) (RIO.AX) lifted force majeure on Jan. 1 for shipments of refined copper and acid from its Kennecott mine in the United States, 79 days after declaring it could not meet customer commitments, a spokesman said on Friday.

The global miner declared force majeure Oct. 13, after halting production of refined copper at its Utah mine smelter following the death of a worker exposed to sulfur dioxide gases at the plant. It restarted the smelter Nov. 17. [L2N1MS0YC] [L1N1NQ1TY]

"It's business as usual," said spokesman Kyle Bennett.

In the fourth quarter, refined copper production at Kennecott declined 67 percent compared with the same period in the previous year, to 22,100 tonnes from 67,000 tonnes, Rio said in an operations report last week. [L3N1PA4KZ]

The smelter was expected to draw down an increased concentrate inventory during the first half of 2018, Rio said.

In 2017, Kennecott produced 125,800 tonnes of refined copper, down some 20 percent from 2016.

(Reporting by Susan Taylor; Editing by Marguerita Choy)