ISO 1920-6:2019

This document specifies a method for taking cores from hardened concrete, their examination, preparation for testing and determination of compressive strength.
This document does not give guidance on the decision to drill cores or on the locations for drilling and does not provide procedures for interpreting the core strength results.
It is recommended that before coring, full agreement should be reached by all parties on the need for core testing and how the results should be interpreted.