Light & Engineering Vol. 23, No. 4, pp. 15-21, 2015 Svetotekhnika No. 4, 2015, pp. 29-33 EXPERIMENTAL RESEARCH OF EVALUATION METHODS FOR COLOUR RENDITION QUALITY Dmitry V. Skums and Lyubov D. Chaikova The Belarus State Institute of Metrology Republic Unitary Enterprise, Minsk, Republic of Belarus E-mails: dmitri_scums@mail.ru, optic@belgim.by ABSTRACT The principles of evaluation of colour rendition quality for energy saving light sources are considered. <...> Results of visual experiments of colour rendition quality evaluation of light-emitting diode light sources are given, and their comparison with theoretical predictions is presented. <...> Possible directions for the modernisation of the CQS method of colour rendition evaluation are shown. <...> Keywords: light-emitting diode light sources, colour rendition index, CIE, CQS INTRODUCTION Up to 20% of electric energy consumed in the Republic of Belarus is used for illumination of streets and rooms [1, 2]. <...> In recent years, compact fl uorescent lamps (CFL) have become widespread. <...> This certainly reduces the economic benefi t of introducing these lamps, and mercury pollutants into the environment. <...> Light-emitting diode light sources (LEDLS) don’t have such disadvantages, and have a number of well documented benefi ts [3, 4]. <...> An analysis of effective technical standard legal acts (TSLA) has shown that light sources colour rendition index (CRI) value is a feature of a number of requirements, and poor performance against prescribed values can prevent the application of such sources. 15 At the same time, there are no TSLAs normalising CRI measurement methods for modern energy saving light sources. <...> The only TSLA normalising measurement methods of chromatic characteristics of light sources is the out-of-date GOST 23198–94 [5]. <...> It is based on the CIE publication of 1974 “Measurement methods and specifi cations of properties of light source colour rendition“, in which the current method is the 1994 version. <...> For similar reasons, the US Department of Energy has recommended not to use CRI as an indicator of LEDLS quality. <...> However, this approach is unacceptable in the Republic of Belarus as some TSLAs regulating CRI values [5, 6] are <...>