DAN News
2008 Tech Diving Conference Workshops Overview
Last Updated: 4/20/2009 5:00:19 PM

• For additional details on the conference and a registration form, click here or click here.

• To become a sponsor for the 2008 Technical Diving Conference, launch the attached Sponsor Pledge Form (see the bottom of this page) and send it to DAN. The address is on the form.

PHYSIOLOGY WORKSHOP PLAN

CNS Oxygen Toxicity
Relevant mechanisms of CNS toxicity: free radicals, ventilation, CO2 retention, cerebral blood flow. Risk factors and individual susceptibility. Donald’s WWII studies. Estimating CNS toxicity risk in relation to O2 exposure, review of O2 exposure guidelines, and the O2 clock. O2-CO2 interactions and “Shallow Water Black-Out.” Mixed-gas O2 exposure limits. Recovery from CNS toxicity risk during underwater air breaks. Case reports.

Narcosis and HPNS
Signs and symptoms of nitrogen narcosis; individual susceptibility, accommodation and adaptation to narcosis; effects on narcosis of rate of compression, oxygen and carbon dioxide; onset depths of narcosis; narcotic potencies of N2, He, Ne, Ar, Xe, O2and CO2; oxygen narcosis; recommended depth limits for air diving; mechanism of narcosis; pressure reversal; utility of EAD/END (equivalent air depth/equivalent nitrogen depth). Signs and symptoms of HPNS; individual susceptibility; depth of occurrence; effect on HPNS of compression rate and time at depth; effect of trimix; effect of hydreliox; mechanisms of HPNS; options for reducing HPNS effects given obligatory fast descent rates.

Thermal Mechanisms of heat transfer (radiation, conduction, evaporation, and convection) with application to divers. Physiological temperature control and consequences of heat transfer (work; shivering; regional vasoconstriction; stages of hyperthermia and hypothermia; freezing and non-freezing injury). Respiratory heat transfer (inert gas and density effects). Rewarming and thermal afterdrop (“warm and dead”). Drysuit insulation properties of Ar, He, CO2, air and O2 (is this safe?). Insulation properties of wet undergarments. Tools for thermal modeling. Hotwater suits for shallow in-water decompression stops vs. insulation for dry decompression. (Thermal effects on decompression will be covered in the Decompression Workshop.) Current and new active and passive technologies (power sources, hydrogen thermal batteries, hydrogen catalytic heating, regional rewarming, aerogel garments).

DECOMPRESSION WORKSHOP PLAN

DCS Risk Factors
VGE as a measure of decompression stress. Environment: temperature, immersion, exercise. Influence of dive phase (pre-, bottom, deco, post-). Individual: obesity, gender, age, aerobic fitness, individual susceptibility. Adaptation, hydration, alcohol, previous DCS, injury.

Deep Stops
History and theory of deep stops. Empirical methods and rules. Supporting evidence and experimental data. Validation of methodology.

In-Water Recompression
Review of IWR experience. Appropriate signs and symptoms for IWR. Equipment and procedures to minimize IWR risk in event of decompression emergency with no access to recompression chamber. Training requirements. Environmental conditions. Depth measurement and control. Diver monitoring and tending. Surface support. Emergency procedures. Outcome reporting.

DCS Risk Assessment
DCS probability and severity in air and nitrox diving. DCS severity and acceptable DCS risk. Technical diving database, risk analysis and dive condition effects. Examples of tech dive profiles and outcome data. Diver Health Status Form (DHSF). Uploading dive profile and DHSF data to DAN Website. Are technical divers self-selected?

REBREATHER WORKSHOP PLAN

Testing should be performed on breathing machines and by divers. What US and EU labs are qualified to test rebreathers? What is the role of failure mode effect and criticality analysis (FMECA) in rebreather design? New U.S. Navy performance standards are based on diver tolerance. U.S. Navy and EU rebreather test standards should not differ, but do.

Manufacturers’ Panel Discussion (selected questions)

• What equipment factors determine the maximum recommended dive depth?

• Is there a role for a full-face mask and communications equipment?

• Should recreational rebreathers be tested by a third-party? Are existing test protocols appropriate for recreational rebreathers?

• Should manufacturers publish unmanned test results such as work of breathing, O2 setpoint tracking, CO2 canister duration, etc.?

• What circumstances warrant open-circuit bailout, vs. closed-circuit bailout, vs. non-bailout?

• Should rebreathers with electronic O2 control turn on automatically to reduce the chance of hypoxia?

• If a rebreather relies on manual rather than automatic O2 control, will hypoxia or hyperoxia be less likely?

• What are the three most important tests for a rebreather involved in an accident?

• If a ‘black-box’ data recording system is incorporated in a rebreather, what should be recorded?

• What are the key points to be observed when recovering a rebreather that was involved in an accident?

• Would standardization of rebreather components be useful (e.g., direction of gas flow, O2 and diluent positions, etc.)?

TRAINING WORKSHOP PLAN

Risk Factors
Review of principal factors associated with fatalities in DAN surveillance data for open circuit, closed-circuit, and cave diving. Factors associated with the most fatalities might be given the greatest emphasis in training to yield the largest reduction in deaths. Review of mishaps correctable by the diver, those requiring assistance by a buddy, and those needing surface support assistance. How do these relate to equipment design, pre-dive checks, and emergency procedure training?

Training Panel Discussion (selected questions)

• What are the three major objectives of training?

• What are the three major issues concerning training?

• What are the three major differences between open- and closed-circuit scuba training in technical diving?

• Is there a need for common training standards?

• What are the prerequisites for technical diving training?

• Is quality control needed for training courses?

• What are three critical errors that training alone may not eliminate?

• Should technical diving training focus on the organization as well as on the individual?

• What is the role of the buddy in technical diving?

• Do physical fitness standards need to be more rigorous for technical diving than for traditional recreational diving?

Thank you for your support and participation!

Additional Resources:
Sponsor_Pledge_Form.pdf