# Regulation (EC) No 1222/2009 of the European Parliament and of the Council of 25 November 2009 on the labelling of tyres with respect to fuel efficiency and other essential parameters (Text with EEA relevance), Division 4.2.8.3: Calculation of the adjusted average peak braking force coefficient

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

The average peak braking force coefficient of the reference tyre used for the calculation of its braking force coefficient is adjusted according to the positioning of each candidate tyre in a given test cycle.
This adjusted average peak braking force coefficient of the reference tyre ( Ra ) is calculated in accordance with table 3 where R 1 is the average peak tyre braking coefficient in the first test of the reference tyre (R) and R 2 is the average peak tyre braking coefficient in the second test of the same reference tyre (R).
Table 3
Number of candidate tyre(s) within one test cycle
Candidate tyre
Ra
1
( R 1 -T1- R 2 )
T1
Ra = 1/2 ( R 1 + R 2 )
2
( R 1 -T1-T2- R 2 )
T1
Ra = 2/3 R 1 + 1/3 R 2
T2
Ra = 1/3 R 1 + 2/3 R 2
3
( R 1 -T1-T2-T3- R 2 )
T1
Ra = 3/4 R 1 + 1/4 R 2
T2
Ra = 1/2 ( R 1 + R 2 )
T3
Ra = 1/4 R 1 + 3/4 R 2

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Source: https://www.legislation.gov.uk/eur/2009/1222/annex/V/division/4/division/4.2/division/4.2.8/division/4.2.8.3 (the official version)
Page: https://openlegislation.uk/eu-regulation-2009-1222/annex-V/division-4/division-4.2/division-4.2.8/division-4.2.8.3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.