Grade 0-No symptoms of chest tightness or breathlessness on Mondays.
Grade 1/2-Occasional chest tightness on Mondays, or mild symptoms such as irritation of
the respiratory tract on Mondays.
Grade 1-Chest tightness and/or breathlessness on Mondays only.
Grade 2-Chest tightness and/or breathlessness on Mondays and other days.