 - Demonstration of an increase in absolute FEV1 of at least 12 and a volume increase of at least 200 mL within 15-20 minutes after administration of 4 inhalations of albuterolsalbutamol total dose 360 to 400 mcg or of nebulized short-acting beta agonist SABA 2.5 mg, if confirmed as standard office practice, OR 