Effect of submarine microclimate on respiratory physiology of submariners: An observational study

Abstract

Introduction: A few personnel feel more tired staying and working inside submarine, as compared to ashore/outdoor spaces, or even onboard afloat platforms (ships). The microclimate onboard underwater platforms play a vital role in determining the respiratory physiology parameters of personnel onboard. There exists a felt need for deeper evidence in this regard. Aims and Objectives: This study is an effort to analyze if there exists any relationship between concentrations of respiratory gases (such as oxygen and carbon dioxide) and other parameters of submarine microclimate, on the respiratory physiology parameters (such as respiratory rate [RR] and SpO2) of personnel onboard underwater platforms. The difference in concentrations of oxygen and carbon dioxide in exhaled air of personnel both inside and outside submarine was also studied. Any difference between smokers and nonsmokers regarding this parameter was also evaluated. Materials and Methods: The study was carried out on thirty healthy volunteers posted onboard a submarine. Concentrations of oxygen and carbon dioxide in the atmosphere, as also the exhaled air, were measured using a digital gas analyzer. Humidity, temperature, and oxygen saturation were measured using digital meters. The values both inside and outside were recorded and compared. Results: There was a statistically significant difference in the temperature, humidity, and level of CO2 inside and outside the submarine. There was no statistically significant difference in level of oxygen in atmosphere, oxygen and carbon dioxide in exhaled air, RR, and SPO2 level inside and outside the submarine. Conclusion: The corrected effective temperature inside a submarine is to be measured periodically and maintained in the comfort zone. The level of CO2 should be maintained close to environmental levels.