It is known, that fractures are caused by stresses. Discontinuities only change the acceptable stress level. This statement was main reason of including of Strain testing method (ST) in ISO 9712-2005[1]. In same year it was included in voluntary certification system of Russian NDT Society (RSNTTD). It was a time of normative documentation vacuum. There are not any codes or standards how to perform stress measurement, what equipment have to be used and what is an acceptance criteria. Only exception was a stress gauge testing method. It was enough codes how to apply this method. Of course it was no any guidelines and codes how to train and certify ST personnel. In the Russian federation measurement of stresses level become an urgent problem. A lot of time from 1985 till 2005 pipelines and other equipment was not properly served. There were no planned inspections, repairing and replacing of old equipment. The economic potential of Russia slowly grows, but, it was impossible to replace all or repair all equipment in one year (to long time system doesn't work and a lot of equipment have to be replaced). To increase the effectiveness of repair and replacement works it was necessary to find equipment in worst condition (include NDT and strain stress measurement result) and repair it first of all.

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