Rebreather Division

Please Note:-
Diving carries many inherent risks. Do not attempt to dive with a closed circuit Rebreather unless qualified to do so.

Fact:
More and more rebreather divers are appearing as each year goes past. In Atlantic Divers our resident tech instructor has prepared the following article for our club members and as a reference for divers who dive with a buddy who uses a rebreather.
NOTE:-Before entering the water with your rebreather buddy a full buddy check must be carried out, in addition a familiarisation of the rebreather operation should be carried out.

It is a known fact that most qualified divers with rescue training have little or even no experience and training on how to rescue an unconscious rebreather diver whilst underwater.
As the diver increases in experience and starts venturing further field and even sometimes deeper, the possibility of encountering a diver in difficulty becomes greater. In the unlikely event you encounter a rebreather diver unconscious on the seabed you shall be able to assist. The following is not a training aid it is merely a guide on how to rescue a diver using an Inspiration rebreather. Seek guidance and training from a qualified rebreather instructor.
At club meetings there will be presentations given on how to carry out a rescue, and those who are diving as a buddy to a rebreather diver will be given in-water training.

Potential Problems: There are many factors which can render a rebreather diver unconscious such as • Breathing wrong mix • Heart failure • Hypoxia (too low oxygen) • Hyperoxia (too high oxygen) • Hypercapnia (too carbon dioxide) • Medical condition

The following steps can assist you in how rescue a rebreather diver in the unlikely event of the diver becoming unconscious underwater.

• Check for responsiveness by grasping the  divers shoulder firmly and shake if, no response lift diver upwards so he faces you and check his eyes-if  no response carry-out the following steps
• Is the divers mouth-piece in place- briefly check, if not in place do not waste time trying to put back in, Note:- Under no circumstances attempt to replace their mouthpiece. Close mouthpiece if in the open position. Immediately lift diver to the surface maintaining an open airway to prevent lung over-expansion.
• If the divers mouthpiece is in place carry to the next step.
• Check if the diver is still breathing by placing a hand on the counter lungs and feel for inhalations and exhalations, the lungs should be expanding and contracting
• Check both gauges if any one shows empty, check tank valves . If diver has no gas stop assessment and immediately lift diver to surface.
• If diluent gas available perform diluent flush, mouthpiece can be retained in divers mouth by placing your head against it and push the divers head back gently to keep the airway open. Both hands are now available to carry out the diluent flush. One hand shall be placed on the diluent button and the other one used to pull on the dump valve for the exhale counter lung, lean diver onto left-hand side down so the dump is at the highest point. Now carry out a diluent flush, this shall now bring a breathable mix back into the loop.
• Check handsets to ensure there a breathable mix in the loop
• Carry out BCL (Buoyant Controlled Lift) secure mouthpiece in place whilst ascending and remember to keep airway open during ascent by gently tilting head back or lung over expansion injury could occur. Ascent rate should not exceed 10 meters per minute.
• Frequently check hand sets throughout ascent to monitor PPO2 in loop during ascent. Carryout diluent flush if mix drops below a breathable content. Beware - As the diver ascends the PPO2 in the mix shall be continually dropping- Hypoxia can occur.
• Keep the diver slightly more positively buoyant than the rescuer.
• Once the surface has been reached establish positive buoyancy by either inflating wing or dropping weight belt. Remove and close mouth-piece and remove mask. Check for breathing – if not breathing give 2 slow full rescue breaths and call for assistance. Egress with diver to shore – whilst maintaining rescue breaths. Remove from water and carry-out required First Aid measures.
• Administer oxygen- can only do good

Ian Reid
Atlantic Divers