Harmonisation of Test Methods for the Execution of the European Construction Products Directive (CPD). Validation of a European Leaching Test for Construction Products

Abstract

CEN/TC 351 “Construction products: Assessment of release of dangerous substances” worked out three drafts for harmonised test methods, which are necessary for the implementation of the Essential Requirement No. 3 “Hygiene, Health and the Environment” of the Construction Products Directive. One of these standards describes the tank leaching test, which is intended for the determination of the leaching of inorganic and organic substances from monolithic construction products. Before the CEN/TC 351 test methods can achieve the status of European standards (EN), robustness testing and, as a second validation step, round robin tests are necessary. In a research project funded by the German Environmental Agency (UBA), the robustness of the tank leaching test was investigated—in agreement with CEN/TC 351—for concrete and mortar. During these investigations, the preliminary storage times of the test specimen, the test temperature, the contact time, etc., were varied. For the mortar, the TOC-release was determined besides inorganic parameters. The results for the potassium-release, the sodium-release and the TOC-release can be interpreted in such a way that the test method by itself is robust. For trace elements and anions, the range of the results is wider; this is probably due to the very low leached amounts for many parameters, which are often near or below the quantification limit.