In public procurement, the issue of technical and functional comparability of products becomes particularly important when it is necessary to substantiate the possibility of using a product whose technical characteristics differ from those of the product designated as the reference model.
Do differences in individual technical characteristics necessarily mean that products cannot be considered equivalent? Is comparing the specifications stated in product data sheets sufficient to establish their interchangeability?
Answering these questions requires more than a formal comparison of technical characteristics. It also requires the application of Special Scientific Knowledge to assess the significance of those characteristics in light of the products’ functional purpose and the specific conditions of their use.
A practical example of this approach is the Independent Professional Expertise in the Form of Conformity Assessment conducted by IPE LLC in the field of Scientific and Technical Expertise. The subject of this expertise was to establish the technical and functional comparability of the WDC 2406 150W 4000K LED streetlight luminaire with the reference VIOLUX CONCORD 150W 19500 lm 5000K IP65 luminaire through a scientific and technical comparative analysis of their characteristics.
The expert research established the technical and functional comparability of these luminaires as lighting fixtures intended for outdoor lighting, including road lighting.
The expert research established that, despite having the same rated power of 150 W, the WDC 2406 150W 4000K luminaire has a higher declared luminous efficacy, a longer declared service life, a wider operating temperature range, and a higher ingress protection rating of IP66 compared with the IP65 rating of the reference luminaire.
For most of the characteristics examined, the specifications of the WDC 2406 150W 4000K luminaire are no lower than the corresponding declared specifications of the reference luminaire and, for certain parameters, are higher. At the same time, differences were identified, particularly in correlated color temperature and declared luminous flux.
Of fundamental importance is the fact that the identified differences do not, in themselves, indicate any deterioration in the functional or operational properties of the WDC 2406 150W 4000K luminaire or its inability to serve an equivalent functional purpose.
At the same time, the results of the expertise made it possible to identify an important limitation in assessing technical equivalence. Establishing the technical and functional comparability of products based on documented characteristics does not automatically confirm their photometric equivalence in a particular lighting installation.
In particular, compliance with regulatory requirements for luminance, illuminance, lighting uniformity, and glare limitation depends not only on the specifications stated in the luminaire’s technical documentation but also on its photometric characteristics, optical system parameters, luminaire arrangement, road geometry, and other design conditions.
Therefore, definitive confirmation of photometric equivalence under specific conditions of use requires appropriate photometric data and/or lighting calculations.
Based on the combination of documented characteristics, the expert research established that the WDC 2406 150W 4000K luminaire may be recognized as a technical equivalent of the VIOLUX CONCORD 150W 19500 lm 5000K IP65 luminaire for use in an equivalent functional application.
However, this conclusion does not automatically confirm that the luminaire complies with all requirements of specific Ukrainian State Building Codes (DBN), Ukrainian National Standards (DSTU), or other regulatory documents, unless such compliance has been the subject of a separate assessment.
Particular attention during the expertise was also given to the identity and interchangeability of different luminaire models manufactured by the same producer.
The research established that the WDC 2501 100W 5000K COB and WDC 2406 150W 4000K luminaires are different models, distinguished by their rated power, correlated color temperature, model configuration, and LED component design.
The fact that products belong to the same brand is not, in itself, sufficient grounds for recognizing them as identical or automatically interchangeable. At the same time, differences between models do not preclude their use for an equivalent functional purpose, provided that such use is supported by an appropriate assessment of their technical, structural, and photometric characteristics.
Thus, the results of the expertise demonstrate that establishing the technical and functional comparability of products in public procurement cannot be reduced to a formal comparison of individual technical parameters or product model designations.
A comprehensive assessment of the products’ documented characteristics, their functional purpose, the identified differences, and the potential impact of those differences on their operational properties is of particular importance.
Accordingly, conducting Independent Professional Expertise in the Form of Conformity Assessment in the field of Scientific and Technical Expertise constitutes an effective preventive mechanism for substantiating public procurement decisions involving the establishment of technical and functional comparability of products.
Obtaining an Expert Opinion before making the relevant procurement decision enables the contracting authority to establish an independent professional evidentiary basis, substantiate the technical equivalence of the proposed products, determine the limits of their potential interchangeability, and identify in a timely manner any issues requiring additional technical verification.
This approach contributes to more thoroughly substantiated procurement decisions, strengthens their evidentiary support, and minimizes the legal and technical risks faced by the public procurement contracting authority.
