1. SWB Shallow Water Blackout By Michelle Brislen

2. What is SWB? Loss of Consciousness while in water Usually caused by hyperventilation while freediving or breath-holding Often happens to freedivers, athletes, and good swimmers. Can happen in the ocean, pools, lakes, rivers, etc. Loss of Consciousness while in water Usually caused by hyperventilation while freediving or breath-holding Often happens to freedivers, athletes, and good swimmers. Can happen in the ocean, pools, lakes, rivers, etc.

3. Hero Worship Image from NY Times

4. Energy Processes Cellular Respiration C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + Energy SugarOxygen Carbon Dioxide Water

5. How does it happen? Release of CO 2 (Carbon Dioxide) through hyperventilation or deep exhales When under water O 2 (Oxygen) is used up and turned in to CO 2 CO 2 is lower than normal because of hyperventilation thus decrease urge to breathe Stay down/under water longer and O 2 continues to be used and deprives brain Blackout occurs Release of CO 2 (Carbon Dioxide) through hyperventilation or deep exhales When under water O 2 (Oxygen) is used up and turned in to CO 2 CO 2 is lower than normal because of hyperventilation thus decrease urge to breathe Stay down/under water longer and O 2 continues to be used and deprives brain Blackout occurs

6. Normal Dive SWB Dive Diagrams from Wikipedia Problem

7. Diagram from Aquatics International Shallow Water Blackout

8. How to Prevent SWB Do not hyperventilate Do not have breath-hold competitions under water Do not perform underwater laps When you feel the urge to breathe, begin your ascent Leave something in the tank! Dive with a Buddy!!!! Maintain watch for 30 seconds after surfacing Be weighted correctly and willing to release your belt if youve pushed it too far. Tell your friends! Adults too! Do not hyperventilate Do not have breath-hold competitions under water Do not perform underwater laps When you feel the urge to breathe, begin your ascent Leave something in the tank! Dive with a Buddy!!!! Maintain watch for 30 seconds after surfacing Be weighted correctly and willing to release your belt if youve pushed it too far. Tell your friends! Adults too!

9. References shallowwaterblackoutprevention.org Confessions of a Freediving Spearo by Sheri Daye; Hawaii Skin Diver Magazine 2010 www.aquaticsafetygroup.com/PDF/DyingforAi rAquaticsInternationalFebruary2005.PDF www.aquaticsafetygroup.com/PDF/ShallowW aterDeathTheCombatEdge2003.pdf www.wikipedia.com shallowwaterblackoutprevention.org Confessions of a Freediving Spearo by Sheri Daye; Hawaii Skin Diver Magazine 2010 www.aquaticsafetygroup.com/PDF/DyingforAi rAquaticsInternationalFebruary2005.PDF www.aquaticsafetygroup.com/PDF/ShallowW aterDeathTheCombatEdge2003.pdf www.wikipedia.com