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BIOLOGY AND HUMAN LIFE 



2. Dust consisting of hard, sharp particles may scratch the 

 delicate linings of the air sacs, exposing them to the entrance of 

 disease microbes. Examples are metal and stone dust and fine 

 sand, produced in industries in which metals are ground and 

 polished, in which sand blasts are used, and in which the chip- 

 ping of metal or stone is carried on. 



3. Dust may carry with it disease germs of various kinds. 

 Street and house dusts are the most common source of this kind 

 of danger. 



A list of the most common occupations in which the danger 

 from dust is an important factor is given below. It is possible 

 in most of the industries to reduce the danger from dust almost 

 to zero, if we take the trouble to do so. 



SOME COMMON OCCUPATIONS IN WHICH DUST IS A SERIOUS 



MENACE TO THE WORKERS 



Mining 



Crushing of metals and minerals 



Sifting of metals 



Molding and core-making 



Grinding and polishing 



Brass-working 



Tool-making 



File-cutting 



Marble-cutting 



Stone-working 



Glass-working 



Cement-working 



Pottery and other earthenware 



industries 

 Plastering and paper-hanging 

 Diamond-cutting 

 Engraving 

 Jewelry-making 

 Grain-handling 

 Flour industry 

 Starch-refining 

 Baking and confectionery work 



Tobacco-working 



Cotton-textile industry 



Flax and linen industries 



Woolen and worsted manufacture 



Silk industry 



Spinning 



Weaving 



Hosiery and knitting industries 



Lace-making 



Hat-making 



Hemp and cordage industries 



Jute and jute-goods industries 



Shoddy manufacture 



Rag-picking and rag-working 



Wood-turning and wood-carving 



Cabinetmaking 



Upholstery and mattress-making 



Brush-making 



Paper-making 



Printing industry 



Lithographing 



Street-cleaning 



