Abstract
Among available standardized test methods for evaluating the performance of marine and offshore
coatings, ISO 20340 Annex A is widely used. 1 It is well known that tests performed on presumably
identical materials in presumably similar circumstances do not in general yield to identical results. Such
deviation is attributed to unavoidable random errors inherent in every test procedure and the fact that
the parameters that may influence the outcome of a test cannot all be completely controlled. One
consequence of such deviation is that different coating selection may be obtained upon where and how
the test is performed, as ISO 20340 Annex A includes acceptance criteria for the selection of coating
systems. Thus, to establish the precision of ISO 20340 Annex A, six laboratories participated in a
round-robin evaluation of ISO 20340 Annex A test method for the first time. The aim was to estimate
the repeatability and the reproducibility of this test upon laboratory, and eventually to determine how to
improve the test method and the standard for the further revision of the standard. Five different painted
systems applied on abrasive blasted steel were selected so that it included good and poor systems.
The results of this study in terms of scribe creep and pull-off strength data were analyzed regarding the
repeatability within a laboratory and lab-to-lab reproducibility.
coatings, ISO 20340 Annex A is widely used. 1 It is well known that tests performed on presumably
identical materials in presumably similar circumstances do not in general yield to identical results. Such
deviation is attributed to unavoidable random errors inherent in every test procedure and the fact that
the parameters that may influence the outcome of a test cannot all be completely controlled. One
consequence of such deviation is that different coating selection may be obtained upon where and how
the test is performed, as ISO 20340 Annex A includes acceptance criteria for the selection of coating
systems. Thus, to establish the precision of ISO 20340 Annex A, six laboratories participated in a
round-robin evaluation of ISO 20340 Annex A test method for the first time. The aim was to estimate
the repeatability and the reproducibility of this test upon laboratory, and eventually to determine how to
improve the test method and the standard for the further revision of the standard. Five different painted
systems applied on abrasive blasted steel were selected so that it included good and poor systems.
The results of this study in terms of scribe creep and pull-off strength data were analyzed regarding the
repeatability within a laboratory and lab-to-lab reproducibility.
