Comparison of foundry dust evaluation by various methods.

Matched sets of dust samples were collected in gray iron foundries for the purpose of comparing results obtained by four sampling techniques. Both respirable and total dust samples were collected. The results are compared on the basis of total concentration and on the basis of silica content. The problems in obtaining an adequate sample for silica analysis are considered. A proposal is made for using total respirable dust as an index of permissible dustiness in foundries.