IV. Sampling and Sample Preservation 



The most important factor in sampling and sample preservation is to 

 retain, in a useable form, all of the information available from the 

 sample until the information can be extracted. The original location, 

 orientation, and appearance of the sample should be documented. The 

 sample should be removed carefully, properly preserved, and transported 

 to the analyzing facility. 



A. Biological Samples. Most biological samples can be removed 



from the structure by careful scraping or other means or they can be 

 removed with the substrate. The samples should then be placed in 

 labeled bottles or jars and covered with ethyl alcohol containing 5% 

 glycerine or with a 5% solution of formalin in water. The containers 

 should be well sealed. 



B. Corrosion Products. Corrosion products can be removed from the 

 structure by careful scraping, or they can be removed with the substrate. 

 The optimum preservation method is to place the products in labeled 

 bottles or jars and covered with fresh seawater. A second method is to 

 place the moistened products in marked plastic bags, subsequently 

 sealed. 



C. Metallic Specimens. Small components should be removed intact; 

 samples from larger components should be removed by sawing, chiseling, 

 or other method. Flame cutting is undesirable but is often necessary. 

 When flame cutting is used, the sample area should be cooled with wet 

 rags or other means, and left with a 2- to 3-inch margin around the area 

 of interest because the heat of the flame can seriously affect the 

 condition of many samples. Small metal samples can be preserved by 

 placing them in labeled bottles or jars and covering them with n-butanol. 

 Larger samples should be rinsed with fresh water, dried, and sealed in 

 marked plastic bags. 



D. Other Materials. Other materials should be removed so as to 

 minimize damage and preserved according to guidance given by personnel 

 with expertise in their handling. 



E. Transport of Samples. The samples should be packaged in sturdy 



wooden crates and transported by air freight or rapid surface transport 

 to the analyzing facility. 



V. Personnel Requirements for On-site Inspection 



A. Basic Requirements 



1. Inspector - a corrosion engineer experienced in evaluating 

 structures after deep-ocean exposure. 



B. Desirable Additional Requirements 



1 . Photographer - person familiar with closeup photographic 



techniques; preferably a qualified, professional. Navy photographer. 



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