The analogy comparing trimix use in recreational diving to parachutes on airliners overlooks a critical distinction. Parachutes address extremely rare, high-consequence failures in the safest industry in existence, while gas density, narcosis, and CO₂ retention affect every diver on every deep dive.
In risk management, not all risks can be eliminated, but they must be visible and understood. Divers must assess their own risk tolerances, yet current recreational diving curricula across Open Water, Advanced Open Water, and Deep Diving certifications from major training agencies fail to address these physiological hazards. At depths between 100 and 130 feet, gas density and CO₂ retention are rarely discussed. As a result, divers are often unaware of the trade-offs they are making or the potential benefits of using helium-based mixes to improve safety.
Citing cost or economic feasibility as the primary reason to avoid trimix use in recreational depths is a flawed approach to safety. Cost is a factor, but it should not be the deciding factor. If cost were the main filter for risk management, we would not use redundant regulators, dive computers, or surface signaling equipment. Many accepted safety practices in diving carry additional costs, yet are widely adopted because they reduce the likelihood or severity of incidents. The value of a mitigation strategy should be based on its ability to reduce risk, not just its price tag.
