PADI Divemaster Certification Practice Exam

What is one challenge associated with using CCRs for diving?

1. They are easy to locate from the surface

2. They can stay down significantly longer than recreational divers

3. They require no prebreathe time

4. They can only be used by advanced divers

The correct answer is: They can stay down significantly longer than recreational divers

The challenge associated with using Closed Circuit Rebreathers (CCRs) lies in their complexity and the specialized training required to operate them safely. While it is a benefit that CCRs allow divers to stay down significantly longer than those using traditional open circuit systems, this extended bottom time also presents challenges. With longer dive durations, there is an increased necessity to manage various factors such as the risk of oxygen toxicity and hypercapnia (the buildup of carbon dioxide). This adds a layer of complexity to dive planning and in-water management. Divers must be trained to monitor the gas composition within the rebreather and to understand how to react to potential issues that may arise during a longer dive. Moreover, divers need to have a thorough understanding of their own physiological limits and the ability to manage decompression schedules effectively, as these become more intricate the longer a diver remains underwater. In summary, while the ability to stay down longer is a key advantage of CCRs, it is coupled with increased responsibilities and challenges that require advanced training and experience, making the use of CCRs more suited for those with specialized skills in diving.