Can Crystalline Salt Reduce the Size of Scuba Equipment?

safe diver quiz

A popular article over last few days is one about crystalline salt that can uptake and store oxygen in high concentration. It was published in Chemical Science by Jonas Sundberg and coauthors from University of Southern Denmark.1 The article describes a synthetized crystalline containing cobalt combined with an organic compound, which has some properties of biological carriers of oxygen like iron-based hemoglobin in mammals or similar copper-based carriers in other animals.

The most significant property of this crystalline is that it binds oxygen reversibly – it can uptake oxygen and release it – and that this process may be controlled.  Professor Christine McKenzie, the leader of the team that synthetized the crystalline, told the Science Daily2 that among other applications:  “When the material is saturated with oxygen, it can be compared to an oxygen tank containing pure oxygen under pressure – the difference is that this material can hold three times as much oxygen. This could be valuable for lung patients who today must carry heavy oxygen tanks with them. But also divers may one day be able to leave the oxygen tanks at home and instead get oxygen from this material as it “filters” and concentrates oxygen from surrounding air or water. A few grains contain enough oxygen for one breath, and as the material can absorb oxygen from the water around the diver and supply the diver with it, the diver will not need to bring more than these few grains.”

The Combined Effects of Increased Levels of Carbon Dioxide and Breathing Resistance Caused by Underwater Breathing Apparatuses

ONR_Book1 (2)Between July 15-17, the Office of Naval Research (ONR) and the Naval Sea Systems Command (NAVSEA) hosted an undersea medicine progress review meeting in Durham, North Carolina. The presentations focused primarily on topics of interest for the Navy, but most of the research also benefits recreational and technical divers. One topic I found particularly interesting concerns the combined effect of increased carbon dioxide levels (CO2) in breathing gas and the breathing resistance that breathing apparatuses impose on divers.

If breathing is unimpeded, slightly increased levels of CO2 pose no problem. However, the more CO2 that is inhaled, the less CO2 can be added, and a larger breathing volume per unit of time will be required to wash out the same amount of CO2. This increase of breathing volumes occurs automatically, successfully washing out the metabolic CO2 and maintaining a nearly normal level of CO2 in arterial blood (even during exercise when the internal metabolic production of CO2 is increased).