Recital 14 clearly refers to ISO 19447 as the only standard for measuring the ice grip index.
Only C1 tyres with ice braking performance level above the threshold as from ISO 19447 can display the 'ice pictogram' on the label.
Recital (9) explains that it is essential to prevent that testing results obtained by market surveillance authorities are different from the testing results declared by the suppliers. This is possible only with the use of a reliable, accurate and reproducible method, and at the condition that no alternate method providing different information is used.
See also question 'Can C2 or C3 tyres labels bear the ice pictogram?'
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