Accession Number : AD0742469

Title :   Semi-Closed Circuit Mixed-Gas Injection Scuba.

Descriptive Note : Final rept.,

Corporate Author : NAVY EXPERIMENTAL DIVING UNIT WASHINGTON D C

Personal Author(s) : Dwyer,J. V.

Report Date : 24 AUG 1955

Pagination or Media Count : 42

Abstract : The research report describes the general class of semi-closed mixed-gas scuba using constant injection, and outlines the problems leading to the analysis. Postulating instantaneous mixing and homogeneous composition, the analysis considers the steady-state bag oxygen level as affected by supply oxygen percentage, injection rate, and oxygen consumption. The analytical equations yield an extensive tabulation of actual values for various conditions, and corresponding performance curves. The analysis also covers a nomographic method of fixing the maximum variation of bag oxygen level. The report discusses: application of the performance curves to constant and variable mass injection systems; use of the nomograph for setting injection rates; mixed-gas diving limits; and conformance of actual equipment to predicted performance. The conclusions are that the report is an extensive analysis of performance characteristics, that it has many applications to work in progress, and that it can serve as a general reference for mixed-gas injection scuba. (Author)

Descriptors :   (*BREATHING APPARATUS, *SCUBA DIVERS), GASES, OXYGEN, OXYGEN CONSUMPTION, PERFORMANCE(ENGINEERING)

Subject Categories : Life Support Systems

Distribution Statement : APPROVED FOR PUBLIC RELEASE