The relationship between silica (7631869) flour exposure and development of silicosis is discussed. Development and characteristics of silicosis are described. Industrial uses for silica flour are reviewed and recommended exposure limits are provided. Published reports of silicosis among exposed workers are summarized, and the findings of studies conducted by NIOSH at two silica flour mills are reviewed. Recommendations are included for exposure monitoring, engineering controls, medical surveillance, work practices, personal protective equipment, worker education, and product labeling.