Scientific diving techniques in restricted overhead environments

Scientific diving is an extremely useful tool for supporting research in environments with restricted access, where remotely operated or autonomous underwater vehicles cannot be used. However, these environments tend to be close to the surface and require the application of advanced diving techniques to ensure that the research is conducted within acceptable safety parameters. The two main techniques discussed are under-ice and cave diving; for each environment the specific hazards are reviewed and methods for mitigating the concomitant risks are detailed. It is concluded that scientific diving operations in these environments can be conducted to acceptable risk levels; however, risk management strategies must outline precisely when and where diving operations are to be prohibited or terminated.