[A theoretical estimation of the safety of dives culminating in an uninterrupted lifting]

It has been shown using the previously developed model of decompression sickness, which determines the cumulative probability of the development of the symptoms of this illness by the exponential equation whose index is the integral function of cumulative risk of damage to all body tissues by bubbles, Fcum(t) = SigmaFn(t), that underwater dives are practically safe if the function Fcum(t) during its growth will not exceed some small value Fcum-max = SigmaFn-max. Using the hypothetical values of parameters of tissues and functions Fn(t), the curves depth-duration for practically safe non-stop dives on respiration with air and with mixtures of oxygen with helium, neon, and argon have been calculated. The distributions of Fn-max values relative to the half-times of washout of the inert gas from tissues have been obtained, which show that the tissues that experience the largest risks of bubble lesions are different for dives of different duration. A comparison of the curves shows that the short-term dives with air are less dangerous and the long-term dives are more dangerous than the dives with helium-oxygen mixture. It has been shown that the least risk of bubble lesions of tissues arises on dives with neon-oxygen mixture and the greatest risk, on dives with argon-oxygen mixture.