A tourist from the Philippines drowned on a commercial snorkelling tour off South Australia's Eyre Peninsula despite the "valiant" resuscitation efforts by those with her at the time, an inquest has been told.
Ardebby Oh Chua had travelled to Australia with her brother and parents for a family holiday in December 2017.
After arriving in Adelaide, they first visited Kangaroo Island and then headed for Port Lincoln where they joined a swimming with the sea lions tour off Blyth Island.
After snorkelling with the group for about 30 to 40 minutes, Ms Chua was noticed to be facedown in the water and not moving.
Others taking part in the tour, including an experienced doctor, began first aid, before returning the 41-year-old to the tour boat and ultimately bringing her to the shore.
While she briefly regained consciousness during those efforts, she was pronounced dead after being admitted to the Tumby Bay Hospital.
At the opening of her inquiry in Port Lincoln on Friday, Coroner Naomi Kereru was told that those who tried to help save Ms Chua's life could not find things on board the tour boat to help.
"There was no defibrillator on board, nor was there any form of adrenaline," counsel assisting Emma Roper said.
"There was no first aid oxygen kit on board."
Ms Roper said Ms Chua's sister remained by her side, holding her hand during the journey back to shore while a retired nurse continued to check for a pulse but could not feel one.
"Efforts to resuscitate Ms Chua valiantly continued throughout the 65 or so minutes it took to get to Tumby Bay," the inquest was told.
Paramedics were waiting their arrival and immediately took over CPR but the woman could not be revived.
Ms Roper said among the issues to be explored by the inquest would be whether the tour company had adequate risk management procedures in place, whether the staff had the proper qualifications and experience to properly supervise the snorkellers and were the participants provided with enough training and supervision.
She said the inquiry would also consider the circumstances that led to Ms Chua being found unresponsive in the water and whether the first aid and rescue supplies on board the tour boat were adequate, given the distance between the vessel and the nearest hospital.
