Nitrogen-Oxygen Mixture Physiology. Phase 5. Added Respiratory Dead Space (Value in Personnel Selection tests) (Physiological Effects Under Diving Conditions)

It was noted that certain divers tended to develop high carbon dioxide levels during work while breathing nitrogen-oxygen mixtures at depth. This tendency is believed related to respiratory sensitivity to carbon dioxide. The latter might thus form the basis of practical personnel selection tests. The use of added respiratory dead space was considered a possible method of testing sensitivity, perhaps with the advantage of accentuating individual differences. The physiological effects of dead space in diving are also of concern in their own right. The study was undertaken to assess the possible value of tests involving dead space under various conditions and to obtain more information about the physiological effects of dead space in diving.