Rebreather Forum 3 Conclusions and Recommendations
After three days of meetings and discussion, Rebreather Forum 3 (RF3) concluded with a two-hour session to reach conclusions and recommendations based on majority vote. For each and every topic discussed, there was clearly a majority, and in many cases, the conclusions were unanimous. The following is an abbreviated summary of the conclusions reached by the forum. A complete report will be issued by the forum in the months to follow. The italic portions are a summary of the conclusions, and non-italic portions are commentary on the summaries.
Training Conclusions: 1) The forum endorsed the use of checklists. 2) The forum recommends that instructors and agencies embrace a leadership role in fostering safety and use of checklists. 3) The forum endorses that minimum training standards be made available publicly. 4) The forum unanimously endorsed currency requirements for rebreather instructors.
The checklists should be used for both the build and post-build/pre-dive portions. Checklists should be available on the internet for easy download, and come from both the training agencies and the manufacturers. Another important caveat to the use of checklists is that the dive community, especially instructors and the training agencies should take a leadership role in the use of checklists. In other words, if it is cool to use a checklist, then maybe more people will.
Clearly throughout the Forum, it was made clear that MANY rebreather incidents could have been avoided by simple use of checklists. More than one speaker described incidents where divers actually jumped in the water with their Rebreathers turned off! It seemed clear to everyone in attendance that checklists could have saved a high percentage of divers from fatal accidents.
Additionally, the forum applauded the certification agencies ANDI, IANTD, and TDI for releasing their training numbers to the public, and encouraged other agencies to do the same. They also endorse the DAN efforts to collect more accident and near-miss data by using online methods. They also support the clear differentiation of “Recreation” and “Technical” sport diving and the training of those modes of sport diving.
Accident Investigation and Data: 1) The forum recommends agencies provide rebreather divers with basic instructions in preserving critical information in the event of an accident. 2) The forum endorsed the concept of a call center to aid in the preservation of and collection of critical information regarding accidents. 3) The forum recommends that the manufacturer of the rebreather be involved with investigation of an incident.
It was an eye-opening presentation by David Concannon, Esq. and Martin Parker (AP Diving) regarding several shortcomings in accident analysis that prompted many of these recommendations. David’s presentation made it painfully clear that data is not being preserved. Frequently when an accident happens, the dive computers with critical information is not ending up in the hands of the people who can actually interpret the data.
Key Design and Testing Elements: 1) The forum recommends all rebreathers incorporate data logging (black-box). 2) Rebreathers should be tested via third-party entities, ideally conforming to an internationally recognized standard. 3) Trained divers should receive more information on operational limits of scrubber durations. 4) There is a need to improve oxygen measurement technology. 5) More research should be done into mouthpiece retaining straps. 6) More research should be done with use of full face mask for sport rebreathers.
Oxygen testing was a recurring topic throughout the forum. Several well-known and extremely knowledgeable speakers discussed the associated topics with current methods of PO2 monitoring. Currently, the galvanic cells (O2 sensors most nitrox divers are familiar with) have limitations. As several people including Dr. Bill Stone and Dr. Richard Pyle noted, there are flaws with the voting logic method of PO2 validation. There were several people in favor of the single cell sensing method, where the single cell has two small orifices immediately next to the sensor membrane. The cell constantly self-validates itself by checking both the pure oxygen and the diluent PO2. In a recreational rebreather, if the cell fails the validations, the diver is told to abort the dive. In a technical rebreather, there would be a redundant single cell in the event of a cell validation failure. This concept was certainly embraced by many people who are much smarter than I am, and I predict that this concept will receive more attention as time goes on. With most rebreathers using voting logic, I think it will take a while before divers embrace something new.
While the forum made many conclusions and recommendations, it is my opinion that several key issues require the diving community as a whole to make some of these proposed changes happen. While the Rebreather Forum was making recommendations for specifically the community of rebreather manufacturers, training agencies, and divers, I think the diving community as a whole can take away from this conference with some key safety factors.