[The dynamic observation of the course of pneumoconiosis in machine engineering workers]. / Nabliudenie v dinamike za techeniem pnevmokonioza u rabochikh mashinostroeniia.

A 25 follow-up of 604 pneumoconiosis patients indicates that in machine-builders of modern production the pneumoconiosis process has a relatively favourable course excluding those workers who are exposed to the effect of large concentrations of quartz-containing dust. The leading factor of risk for advancing of fibrosis is tuberculous infection.