Pleural abnormalities of 119 occupationally asbestos-exposed with prominent internal stripe of the lateral thoracic wall were radiodiagnostically analysed by plain films of the thorax in four views and by computed tomography in the course of medical expert's certification. Abnormalities were coded according to 1980 ILO international classification of pneumoconioses. Hardly half of the patients had pleural abnormalities caused by asbestos exposure: Pleural plaques, "diffuse" pleural fibrosis, pleural effusions, organized pleural effusions and pleural tumors. The other half of the patients had pleural involvement of pulmonary and chest wall abnormalities or variations of the lateral thoracic wall not related to asbestos exposure. The 1980 ILO classification of pneumoconioses proved to be inadequate for complete coding of the abnormalities, since only the postero-anterior plain film of the thorax must be used, since the normal appearance of the pleura is insufficiently defined and since the entity of organized pleural effusion is lacking.