Correlation of the achieved rating value with the sustainability class: Range of rating Sustainability values (%) class <79 S1 >79 - <87 S2 >87 - <96 S3 >96 - <104 S4 >104 - <113 S5 >113 - <121 S6 >121 S7 8.2. RATING OF WCs For the rating of the product according to UNE-EN 16578 Annex B (Evaluation scheme), all the ranges of manufactured WCs were taken into account. Rating according to EN 16578 (WCs) WC 1 WC 2 WC 3 WC 4 Average flush volume per WC 3,75 L (suite) 3,38 L (suite) 2,50 L (suite) 3,38 L (suite) Name / Product Type 6/3 WC 4,5/3 WC 4/2 WC WC Intank A893301000 Part 1: Ecological criteria (4.2.) 103 % 103 % 103 % 103 % Part 2: Economic criteria (4.3.) 125 % 129 % 137 % 113 % Part 3: Social and Functional Criteria (4.4.) 93 % 93 % 93 % 93% Full rating 109 % 110 % 113 % 105 % Sustainability class S5 S5 S5 S5 Environmental product declaration. Vitreous china.