Coronial
WAcommunity

Inquest into the Death of Syoko Tsubaki

Deceased

Syoko Tsubaki

Demographics

24y, female

Date of death

1998-12-31

Finding date

2000-05-18

Cause of death

Immersion (drowning due to hypoxic brain injury)

AI-generated summary

Syoko Tsubaki, a 24-year-old Japanese tourist and inexperienced recreational diver, died from drowning on 31 December 1998 after a scuba diving incident at Rottnest Island on 27 December. During an afternoon dive, the dive guide Kazumasa Miyahara ascended with the deceased when her air supply became critically low, but left her alone while returning to collect the remaining four divers who had not surfaced. The deceased encountered difficulties and was found floating face-down approximately 10-15 minutes later. She was resuscitated by rescue personnel but suffered severe hypoxic brain injury and died from the effects of immersion. Key failures included: the dive guide navigating the group 100-150 metres from the vessel, ascending without ensuring all divers surfaced together, failing to ensure proper buddy pairing and communication, and critically, abandoning the distressed diver alone in choppy conditions. The coroner concluded the death was accidental and supported recommendations for industry-wide safety standards including mandatory rescue craft provision and proper dive guide protocols.

AI-generated summary and tagging — may contain inaccuracies; refer to original finding for legal purposes. Report an inaccuracy.

Specialties

diving medicineemergency medicineintensive careretrieval medicine

Error types

communicationproceduralsystem

Clinical conditions

hypoxic brain injurycerebral oedemabrain deathdrowning

Procedures

scuba divingcardiopulmonary resuscitationexpired air resuscitationendotracheal intubationcomputerised tomography of cranium

Contributing factors

  • Dive guide navigated group 100-150 metres behind vessel in choppy conditions
  • Dive guide ascended with deceased without ensuring remaining divers also surfaced
  • Dive guide abandoned deceased in difficulties while returning to locate other divers
  • Failure to maintain buddy system and 'one up all up' principle
  • Inadequate communication regarding group ascent procedures
  • Deceased left alone in water for 10-15 minutes
  • Deceased was inexperienced novice diver in protected environment only
  • Deceased consumed air faster than other divers
  • Deceased had experienced mask difficulty on earlier dive same day
  • Sea sickness affecting deceased before and potentially during dive
  • Choppy sea conditions with waves 1.25-2.5 metres and 25 knot winds
  • Delayed recognition by dive guide that deceased was in difficulties
  • Failure of dive guide to alert rescue vessel personnel immediately

Coroner's recommendations

  1. Support the recommendations of the Underwater Recreational Diving Task Force
  2. Develop a peak body or dive industry forum to monitor training, assist with government policy, represent the industry, and disseminate information
  3. Develop a code of practice detailing minimum safety management practices for underwater recreational diving
  4. Require all professional diving operators conducting recreational dives to have a rescue craft ready for immediate use before divers enter water
  5. For operators taking relatively inexperienced divers, consider requirement to provide suitably trained dive guides or experienced diving buddies familiar with local environment and with reasonable core competencies
Full text
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Source and disclaimer

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