Lung function tests may be helpful, but usually not until the late stages. The medical should be repeated periodically as circumstances may demand. Prevention Reduction of the dust to the lowest level practicable and where necessary by the provision of personal respiratory protective equipment. Asbestosis is a reaction of the lung to the presence of asbestos fibres which, having reached the bronchioles and air sacs, cause a fibrous thickening in the network distribution, mainly in the lower parts of the lung. Among those at risk are persons engaged in milling the ore, the manufacture of asbestos products, lagging, asbestos spraying, building, demolition, and laundering of asbestos worker's overalls.
Symptoms develop slowly after a period of exposure which can vary from a few to many years.
In some cases exposure may have begun so long ago that it cannot be recalled. Breathlessness occurs first and progresses as the lung loses its elasticity. There may be little or no cough and chest pain seldom occurs. The individual becomes weak and distressed on effort and, eventually, even at rest. Unless periodic medicals are introduced the diagnosis will not be made until symptoms appear.