The child labor coverage provisions contained in sections 12(a) and 12(c) of the Act may be jointly applicable in certain situations. For example, a manufacturer of women's dresses who ships them in interstate commerce, employs a minor under 16 years of age who gathers and bundles scraps of material in the cutting room of the plant. Since the employment of the minor under such circumstances constitutes oppressive child labor and involves the production of goods for commerce, the direct prohibition of section 12(c) is applicable to the case. In addition, section 12(a) also applies to the manufacturer if the dresses are removed from the establishment during the course of the minor's employment or within 30 days thereafter. To illustrate further, suppose that a transportation company employs a 17-year-old boy as helper on a truck used for hauling materials between railroads and the plants of its customers who are engaged in producing goods for shipment in commerce. The employment of the minor as helper on a truck is oppressive child labor because such occupation has been declared particularly hazardous by the Secretary for children between 16 and 18 years of age. Since his occupation involves the transportation of goods which are moving in interstate commerce, his employment in such occupation by the transportation company is, therefore, directly prohibited by the terms of section 12(c). If the minor's duties in this case should, for example, include loading and unloading the truck at the establishments of the customers of his employer, then the provisions of section 12(a) might be applicable with respect to such customers. This would be true where any goods which they produce and ship in commerce are removed from the producing establishment within 30 days after the minor's employment there.