Technical diving, and technical mixed-gas diving in particular, presents divers with increased risks and a unique set of hazards. Mixed-gas divers need to manage complex equipment, multiple breathing gases, and mitigate their risk of narcosis and the hazards caused by increased gas density by replacing some, or all, of the nitrogen in their breathing gas with helium. This use of high-content helium gases requires special considerations for gas switching and an adjustment of ascent rates and decompression time, and it can pose additional risks.

In isolated locations without the industry or population required to support medical facilities equipped to deal with dive related emergencies, in-water recompression (IWR) becomes an attractive prospect for dealing with decompression sickness, and a hotly debated issue.