11. After the post-provocation spirometry (two minutes after the provocation), salbutamol, Ventolin 0,1mg meter dose inhaler by Volumatic will be given for reversibility test; 2 puffs for patients weighing less than 45 kg, and 4 puffs for patients weighing 45 kg and more; one puff at a time; 5 inhalations per puff. New spirometry will be performed 5 minutes after giving Ventolin, and FEV1 is registered again, in absolute value, and percentage of the first value, before cold air provocation.