as indicated in section IV below. As the pace of the inspection at this 

 stage should be fairly rapid it is preferable that the sampling be 

 performed by assistants at the direction of the inspector. 



Documentation at this stage of the inspection is both difficult and 

 vitally important. Visual observations should be recorded in writing or 

 on tape. Careful attention must be given to the location of the areas 

 inspected in order to properly interpret the observations. Photographs 

 should be taken at this stage by the inspector or at his direction. 

 Overall and closeup color photographs should be taken and, if practical, 

 also black and white photographs. The locations of the areas photographed, 

 especially the closeups, should be carefully identified and recorded. 



After the initial inspection, sampling, and photographing of the 

 structure are complete, the structure should be carefully rinsed with 

 fresh water. 



III. Detailed Inspection 



This stage of the inspection can be performed at a more deliberate 

 pace than the initial stage, as the appearance of corrosion products and 

 biological growth is not as important at this stage. The primary objective 

 of this inspection is the discovery of hidden damage, the identification 

 of the type of the attack, and an assessment of the extent of damage to 

 the structure by corrosion or other causes. Hidden attack is most often 

 discovered by disassembly of the structure. Crevice corrosion can often 

 be located by bleeding of corrosion products from crevice areas. The 

 type of attack can often be identified by inspection (uniform attack, 

 pitting, crevice corrosion, etc). However, some forms of attack must be 

 verified by laboratory analysis (intergranular attack, stress corrosion 

 cracking, hydrogen embrittlement, etc). The assessment of the extent of 

 damage should be made by both subjective observation and by quantitative 

 measurement of section thickness, depth of pitting, etc. Damage due to 

 causes other than corrosion such as impact, overload, etc. , should be 

 identified. 



Samples of the structural components should be taken at this time 

 for further laboratory analysis to verify the type and extent of damage. 

 Samples should be removed and preserved as indicated in section IV 

 below. This removal and preparation can be done by the inspector in 

 many cases, however, as it may involve the use of power tools or flame 

 cutting equipment, assistance from other personnel is often required. 



Documentation of this stage of the inspection is important but the 

 slower pace makes this duty easier to perform than initial inspection. 

 Visual observations should be recorded in writing or on tape. Careful 

 attention must be given to the location of the areas inspected in order 

 to properly interpret the observations. Photographic documentation 

 should be performed at this stage to record the extent of damage to the 

 structure. Again, indexing of the photographs is important. 



After this stage of the inspection the structure should be retained, 

 if practical, for possible future analysis. 



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