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Recreational and technical rebreather fatalities and diving safety status
Frauke Tillmans1,2,3, Camilo Saraiva1, Sherri Ferguson1,4
1Divers Alert Network, 6 West Colony Place, Durham, NC, USA.
Introduction:
The Divers Alert Network (DAN) aims to provide safety information for all types of diving. Assessing the number of active closed-circuit rebreather (CCR) divers is difficult, as pertinent information is often not available. This review aims to give an overview of global use and safety of CCR diving equipment from 2013-2022.
Methods:
Data were combined and assessed from various DAN internal and public sources on CCR diver demographics, fatalities, and CCR sales.
Results:
Over the past 10 years, the number of certified CCR divers has increased from an estimated 2,000 in 2013, to 3,000 in 2022. There has been an increase in growth in CCR sales over a five-year period from 2018, with around 25,000 to 35,000 units on the market today; rebreather divers are a growing community. There were 241 confirmed CCR fatalities from 2013-2022, mean 24 (SD 6) per year. Most fatal accidents involved dives made between 40-80 m (130-260 ft) depth. Cause of death is difficult to establish due to lack of detail and dive-specific training for the medical examiner. The estimated death rate is 1.8-3.8 deaths per 100,000 CCR dives although these values are derived from limited data.
Conclusions:
Not enough information is made available to address CCR accident analysis effectively, perhaps stemming from family reticence to discuss the incident, fear of litigation, and/or lack of diving knowledge reducing the useful information. DAN continues to collect CCR data, but increased collaboration between training bodies, equipment providers, and comprehensive reporting of incidents is needed to reveal the true picture.
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