LIFE SUPPORT AND HABITABILITY 



In order to survive and function efficiently 

 within their sealed chamber, the submers- 

 ible's occupants require a supply of food and 

 oxygen and removal or storage of toxic 

 gasses which they and their equipment gen- 

 erate. Survival, however, is only the first 

 requirement; the second is the ability to 

 work efficiently and comfortably. The first 

 requirement is termed life support and the 

 second may be referred to as habitability. 



While there is overlapping between life 

 support and habitability, a distinction is 

 made between the requirements and proce- 

 dures to support life versus the quality of 

 life. In engineering circles, the latter subject 

 is termed "Human Factors" and it not only 



embodies comfort, but safety and efficiency 

 as well. 



LIFE SUPPORT 



In designing a submersible life support 

 system a "Standard Man" may be used ; the 

 characteristics of this hypothetical human 

 are presented in Table 9.1. According to the 

 Marine Technology Society's Undersea Vehi- 

 cle Committee (1), the values are conserva- 

 tive and their use in designing a life support 

 system will usually result in a system with 

 satisfactory performance. The standard 

 man's values are predicated on the assump- 

 tion that he will be engaged in very light 



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