En experimentell studie över brand i lagerlokaler med sprinklersystem presenteras. Fyra storskaliga tester med Standard klass II gjordes. This report describes an experimental study of rack storage fires with in-rack sprinklers. Four large-scale tests with Standard Class II commodity, which consists of double triwall corrugated paper cartons, were carried out. Two fast response in-rack sprinkler heads were mounted in the flue at two heights. Measurements of heat release rate, in-rack flame height, excess gas temperature, gas velocity, plume profiles and activation times of the in-rack sprinklers are presented. Comparison of the measured data against axi-symmetric power law correlations for the in-rack plume flow was carried out.