NBN EN ISO 13632:2012

This International Standard specifies a procedure for sampling of rosin and rosin derivatives from
— drums,
— the molten/ liquid form,
— flakes, pellets or pastilles
and preparation of the samples for colour measurement. The method to be used for the colour measurement is specified in other standards. The colour of the rosin can be measured with neat rosin or rosin in solution.
The two most commonly used colour-measurement methods are those based on the USDA1) scale and the Gardner colour scale. Annex A provides information on the correlation between these two scales.