DESIGN OF THE SEALAB II HABITAT 



45 



create CO2 pockets or concentrations. Storage space is provided for replacement supplies of 

 charcoal and LiOH. 



BREATfflNG GAS SYSTEMS 



General 



The breathing gases to be used to make up the Sealab II atmosphere are stored externally 

 in 1,300-cu-ft cylinders (Fig. 25) (approximately 21 ft long and 9-5/8 in. O. D.) Storage pres- 

 sures are nominally 2400 psi and all high pressure lines are designed for 3000 psi service. All 

 breathing- gas systems are cleaned in accordance with BuShips specifications for breathing- 

 oxygen service. Gases for the emergency make-up systems are supplied through the umbilical 

 cord at a maximum pressure of 400 psi. A gas-control panel is provided and contains all com- 

 ponents indicated on each drawing of the individual systems. This panel is located above the 

 counter, port side, aft of the air-conditioning space, and has complete piping- diagram layouts 

 of each gas system properly color- coded for ease of identification. The three pressure regu- 

 lators plus one spare required in the oxygen, helium, and BIBB systems are of the type used in 

 standard welding equipment. All regulators are identical, so as to provide inter changeability. 

 These regulators are capable of providing the specified low pressure (gage) range by simple 

 external adjustment in an ambient pressure of up to 140 psia. 



Fig. 25. Aquanaut Sheets checks fittings on the Sea- 

 lab II externally mounted breathing gas cylinders 



