(A) The following occupations involved in the manufacture of clay construction products and of silica refractory products are prohibited for minors under eighteen years of age, unless exempt by the following:
(1) All work in or about establishments in which clay construction products are manufactured, except (a) work in storage and shipping; (b) work in offices, laboratories, and storerooms; and (c) work in the drying departments of plants manufacturing sewer pipe.
(2) All work in or about establishments in which silica brick or other silica refractories are manufactured, except work in offices.
(1) The term "clay construction products" shall mean the following clay products: brick, hollow structural tile, sewer pipe, and kindred products, refractories, and other clay products such as architectural terra cotta, glazed structural tile, roofing tile, stove lining, chimney pipes and tops, wall coping, and drain tile. The term shall not include the following non-structural-bearing clay products: ceramic, floor and wall tile, mosaic tile, glazed and enameled tile, faience, and similar tile; nor shall the term include non-clay construction products such as sand-lime brick, glass brick, or non-clay refractories.
(2) The term "silica brick or other silica refractories" shall mean refractory products produced from raw materials containing free silica as their main constituent.