International civil engineering firms are changing their strategies more and more from the capacity of execution of construction work to the position of general administrators or even the financing and operation of the structure. Examples of this are the international airport in Athens, or bridge and tunnel projects for international infrastructure. Hence the engineering company adopts a much larger area of responsibility with regard to risks in the planning, the construction and the use of the building than was previously customary. The use of non-destructive testing which can be brought into operation at various stages in the lifetime of the structure for the verification of the working capacity, the stability and the fatigue limit are therefore necessary for the contractor. Areas for testing include: 1. investigation of soil conditions; 2. securing of the soil; 3. quality guarantee during construction; 4. evaluation of the actual conditions after the completion of the construction work; 5. establishment of the required level of maintenance; 6. verification of the effectiveness of the maintenance. The demand for exactness of evidence, reliability of testing methods and reproducibility of results depends on the measured results. When information on the stability of a structural member is required, a very high standard of the trustworthiness of the measured results is required. The acceptance of non-destructive testing during the construction stages of the structures can be improved when the client includes a mandatory clause, in the invitation to tender, of which measurements are to be carried out. The measurement methods need to be clearly and unequivocally laid out and the costs of the measurement would therefore be included in each tender offer. In order to achieve this, a standardisation of testing methods is required, through which the client lays out precisely the required capacity and efficiency, as well as an estimation of the reproducibility.
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