Characterisation of activated reactor components is a multifaceted effort, which include both experimental work and activation calculations which together form a comprehensive characterisation approach. However, both the experimental work and activation calculations have their constraints and uncertainties. This work presents the characterisation of a highly activated stainless steel pipe including sampling planning, sampling, sub-sampling, elemental and radionuclide analyses, and activation calculations. 55Fe, 63Ni and 60Co analyses were carried out in a trilateral intercomparison exercise and the results were compared with activation calculations. The results showed excellent alignment between experimental and activation calculation results.