The use of spirometry is not yet widespread enough in chronic respiratory or at -risk patients whose diagnosis is incomplete. There is scarce knowledge and inadequate management of the burden of these diseases, particularly chronic obstructive pulmonary disease (COPD). Pneumobil, an initiative aimed at raising awareness among smokers and ex -smokers, was reactivated 10 years after its launch in Portugal. It found a large prevalence of bronchial obstruction as measured by spirometry (30% and 25% in men and women respectively) in a sample of 5324 smoke -exposed individuals, 50% current smokers, screened at state or business (private company group) health institutions. This risk is neither mainly attributable to occupational exposure nor mainly related to respiratory symptoms, which were very common in our population. Only dyspnoea (OR=1.28; p=0.02) and frequent episodes of sputum production (OR=1.21; p=0.008) or acute bronchitis (OR=1.31; p=0.05) were somewhat related to bronchial obstruction. Prior knowledge of COPD is rare and bronchial obstruction is not correlated (p=0.204) to a possible diagnosis of COPD.