The most important industrial hazard in those industries in which silica is encountered: namely, pottery, sandstone, sand-blasting, metal-grinding, tin-mining and anthracite coal-mining. It is a specific form of PNEUMOCONIOSIS caused by the inhalation of free silica. The lungs become fibrosed and inefficient, resulting in slowly progressive shortness of breath. The main danger, however, is that it is liable to be complicated by TUBERCULOSIS.

The incidence of silicosis is reduced by adequate ventilation to draw off dust, and its suppression with water; the wearing of respirators where the risk is particularly great; and periodic medical examination of workpeople exposed to risk. Fewer than 100 new cases a year are now diagnosed in the United Kingdom. (See also OCCUPATIONAL HEALTH, MEDICINE AND DISEASES.)