RESPIRATORY GASES USED IN PROFESSIONAL DIVING

An important role in the conception, design, manufacture and operation of underwater breathing apparatuses is played by the breathing gases used in these apparatuses. The type of breathing gas used is imposed by the type of diving device used and the diving technology adopted. For the correct choice of breathing gases in the various underwater breathing apparatuses and for the precise establishment of the diving technology, it is necessary to know in detail the physical characteristics of the gases used

Mathematical Modeling of the Processes Occurring in Gas Mixtures Used in Hyperbaric Facilities

AbstractDiving is one of the domains in which humans are facing a totally different environment from that in which they live normally. Depending on the purpose of the underwater mission and the diving depth to be reached, some special installations and breathable gas mixtures are used to sustain life in such an environment. Diving chambers are hyperbaric facilities used for forming, training, testing and in unfortunate circumstances rescuing divers. The paper deals with the mathematical modeling of the phenomenon taking place in a hyperbaric facility during the compression and decompression phases of a saturation diving. For this purpose the authors of the present paper have conceived a mathematical model with which, the values of the main quantities forming a breathable gas mixtures delivered to the divers are established for each diving depth during the entire mission

Predictions on the dynamic behaviour of an aeroelastic model of a television tower in the boundary layer wind tunnel

This paper presents the process of making a set of vibration measurements on a model of a television tower in the boundary layer wind tunnel. The main objective of the study is to predict the dynamic behaviour of the full-scale structure under the turbulent wind action, specific for the Bucharest site, in Romania. Wind tunnel tests were performed on a 1:500 scale aeroelastic model, existing at the Aerodynamics and Wind Engineering Laboratory “Constantin Iamandi” from the Technical University of Civil Engineering Bucharest. As a result of the vibration measurements on the tower's model, the dynamic behaviour of the structure on the real scale could be determined by using the conditions and relationships of similitude established between the two, model and prototype (full-scale structure). The experimental analysis made in this study may be very important not only in assessing the dynamic response for a building of such importance, during the preliminary stages, but also can be very helpful for the decision makers involved in the design process to choose which is the best solution for such high and slender structures under the action of turbulent wind

IN MEMORIAM Profesor universitar dr. doc. ing. Augustin Iuliu PETRE

Profesor universitar dr. doc. ing. Augustin Iuliu PETRE (13 noiembrie 1923 - 6 ianuarie 1999

THE PROCEDURE BY EVALUATION OF DIVERS FOR THE DEEP DIVING

When a diver is selected to perform a deep diving course, he has to pass a medical test and isn’t affected by the HPNS (High Pressure Nervous Syndrome). When a diver is selected to perform a deep diving course, he has to pass an evaluation stage in order to prove his ability to tolerate the compression speed accompanied by the helium - oxygen breathing mixture without encountering the HPNS effects. The deep diving test consists in postural tremor and the EEG registration, in both conditions: at the atmospheric pressure and at 180 m deep too. Then the results obtained at the surface percentage limits are fixed for the maximum deflection agreed between the values registration made under pressure and the atmospheric pressure (surface) values

HYPERBARIC OXYGEN THERAPY (HBOT) AS A PRACTICE OF THE SCIENTIFIC HYPERBARIC MEDICINE AND ENGINEERING

Assuming that the great number of opportunities that facilitate underwater work revealed new physiological and pathological aspects of immersion and life in hyperbaric conditions we consider that the information contained in this paper is up-to-date in terms of medical and engineering practice. Working in hyperbaric conditions, more or less hostile and abnormal to humans, causes disruptions of the homeostasis, changes, and even perturbations in body functions, which must be reduced through proper methodology. These can and must be diminished through adequate methodology. The use of hyperbaric oxygen therapy has been approached, initially, in France and the Netherlands. HBOT, i.e. HBOT, performed at pressures of 2÷5 atm. abs. is still in its infancy. The theme supposes a monitored hyperbaric chamber able to meet the provisions of the SR EN 14931 of 2006 standard. Within the objectives pursued, the hyperbaric laboratory designated to simulate a dive to a depth of 500 m (50 bar man.) will enable treatments using HBOT for various diseases. The Hyperbaric Laboratory is based on a French standard COMEX unit experienced in deep diving and on the worldwide research results in diving. The hyperbaric complex will meet the goals we have in view within the highest standards and parameters