Editing Trimix (breathing gas) (section)

==Disadvantages of the helium==
Helium conducts heat six times faster than air, so helium-breathing divers often carry a separate supply of a different gas to inflate [[drysuit]]s. This is to avoid the risk of hypothermia caused by using helium as inflator gas. [[Argon]], carried in a small, separate tank connected only to the inflator of the drysuit, is preferred to air, since air conducts heat 50% faster than argon.<ref name="engtbox" /> Dry suits (if used together with a buoyancy compensator) still require a minimum of inflation to avoid "[[suit squeeze]]", i.e. injury to skin caused by pinching by tight dry suit folds.

Helium diffuses into tissues (called [[ingassing]]) more rapidly than nitrogen as the ambient pressure is increased. A consequence of the higher loading in some tissues is that some [[decompression algorithm]]s require deeper [[decompression stops]] than a similar pressure exposure dive using air, and helium is more likely to come out of solution and cause [[decompression sickness]] following a fast ascent.<ref name="Fock 2007" />

In addition to physiological disadvantages, the use of trimix also has economic and logistic disadvantages. The price of helium increased by over 51% between the years 2000 and 2011.<ref name="usgshestats" /> This price increase affects open-circuit divers more than closed-circuit divers due to the larger volume of helium consumed on a typical trimix dive. Additionally, as trimix fills require more expensive helium analysis equipment than air and nitrox fills, there are fewer trimix filling stations. The relative scarcity of trimix filling stations may necessitate going far out of one's way in order to procure the necessary mix for a deep dive that requires the gas.