The concentration of dust inhaled by textile workers is a function of the facility design, the type, age, and condition of processing equipment, as well as the engineering controls and work practices utilized in the particular factory. Even if much data suggest that endotoxin is the causative agent of the disease, reduction of dust will also reduce endotoxin levels. Therefore, the goal of airborne dust reduction should be vigorously pursued.
The principal means to control dust emissions from modern processing equipment is local exhaust ventilation. Older machines usually lack this. General ventilation, sometimes called dilution ventilation, is not as effective as local exhaust ventilation to reduce airborne dust concentrations. Retrofitting older machinery with local exhaust ventilation requires engineering skills and fiscal resources. Although engineering controls remain the preferred top of the "hierarchy of controls" options, maintenance of machinery, elimination of compressed air for cleaning, and wet sweeping also help to reduce airborne dust. Personal protective equipment-i.e., respirators, are also useful, but can be uncomfortable and require attention to fit in order to eliminate leakage.
Workgroup members expressed expectations for slow, incremental progress in reducing dust exposure levels. Small workplaces present the greatest difficulties. Owing to limitations of economic resources, it is unlikely that engineering controls will be retrofitted to older machinery, or that new machinery with dust controls will rapidly replace older machinery. The industries are generally in older buildings and the workforce is not aware of the hazard. Although permissible exposure limits and laws exist in each country, the legally adopted standards vary from 10 mg/m3 total dust (China), proposed to be reduced to 3 mg/m3 (total dust), to 1 mg/m3 respirable