Scope and Applicability of the Proficiency Testing Scheme

The Proficiency Testing (PT) scheme PTS 26_02-T-1 – “Testing of Waterproofing: Tensile Adhesion Strength (Pull-off)”, covering the determination of tensile adhesion strength between waterproofing systems and concrete substrates, is applicable exclusively within the Republic of Bulgaria.

This limitation is purely technical and methodological in nature and is not related to participant eligibility or any form of discrimination. The PT scheme is based on a Bulgarian national testing method, defined in Bulgarian technical rules and normative documents (Appendix 1), which are nationally applicable and not harmonized for international use. As a result, the method cannot be consistently or technically applied by laboratories operating under different national regulatory frameworks.

The scheme is organized and conducted in full compliance with ISO/IEC 17043 and is implemented as a sequential on-site proficiency testing scheme. All participant measurements are performed one after another, at a single designated testing location, using a common prepared test object, under strictly controlled environmental conditions. This design ensures equal testing conditions, high comparability of results, and robust statistical evaluation.

The restriction of the scheme’s applicability to Bulgaria therefore reflects regulatory and methodological specificity only and does not constitute discrimination based on nationality, accreditation status, or any other non-technical criterion. Any laboratory operating within the Bulgarian regulatory context and applying the specified national method may participate under equal and non-discriminatory conditions.