Which testing is included in pre-dive checks for surface-supplied operations?

• A. Visual inspection of lines only
• B. Verification of comms and signal line status
• C. Availability and functionality of bailout gas, retrieval devices, surface-supplied system
• D. No tests required

Answer: (C)

In surface-supplied diving, pre-dive checks focus on confirming that the emergency and primary support systems are ready to keep the diver safe. The best choice is to verify that bailout gas is available and functional, retrieval devices are ready, and the surface-supplied system is working. This trio covers the critical safety gaps: bailout gas provides a backup breathing supply if the main line fails, retrieval devices enable swift recovery of the diver, and the surface-supplied system itself must be tested for proper gas delivery, pressure, and reliability. While visual inspections of lines and checks of communications are important supporting steps, they don’t alone guarantee the essential capability to sustain a diver and recover them if something goes wrong. Saying no tests are required is not appropriate for a safety-critical operation.