LAS VEGAS >> Authorities say a Las Vegas spa worker suffocated in a cryotherapy chamber and her death was an accident.

The Clark County coroner’s office ruled Tuesday that 24-year-old Chelsea Patricia Ake-Salvacion, who had moved to Las Vegas from Hawaii, died from asphyxia caused by low oxygen levels.

She was found on Oct. 20 at the spa where she worked after apparently entering the treatment chamber chilled by liquid nitrogen while she was alone at the location the night before.

Normal air is about 21 percent oxygen, but the coroner said the chambers can bring down the oxygen levels to less than 5 percent during treatments.

Breathing that air could cause a loss of consciousness and death.

The death has drawn attention to the unregulated, unproven treatments that are gaining worldwide popularity.