# Commission Regulation (EC) No 761/2009 of 23 July 2009 amending, for the purpose of its adaptation to technical progress, Regulation (EC) No 440/2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) (Text with EEA relevance), Division 2.2.2: Yield

Extent: E+W+S+N.I.

Effects on yield are determined on the basis of two measurement variables, frond number and one other measurement variable (total frond area, dry weight or fresh weight) present in each test vessel at the start and end of the test. For dry weight or fresh weight, the starting biomass is determined on the basis of a sample of fronds taken from the same batch used to inoculate the test vessels (see second paragraph in section 1.7.3). For each test concentration and control, calculate a mean value for yield along with variance estimates. The mean percentage inhibition in yield (% Iy) may be calculated for each treatment group as follows:
% I y = ( b C – b T ) b C × 100
where:
— % Iy: percentage reduction in yield
— bC: final biomass minus starting biomass for the control group
— bT: final biomass minus starting biomass in the treatment group

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Source: https://www.legislation.gov.uk/eur/2009/761/annex/VI/division/2/division/2.2/division/2.2.2 (the official version)
Page: https://openlegislation.uk/eu-regulation-2009-761/annex-VI/division-2/division-2.2/division-2.2.2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.