29 CFR §776.15

1. (a)The statutory provisions. The activities constituting “production” within the meaning of the phrase “engaged in * * * production of goods for commerce” are defined in the Act 52 as follows:
2. (b)General scope of “production” coverage. The statutory provisions quoted in paragraph (a) of this section, show that for purposes of the Act, wherever goods are being produced for interstate or foreign commerce, the employees who are covered as “engaged in the production” of such goods, include, in general, all those whose work may fairly be said to be a part of their employer's production of such goods, 55 and include those whose work is closely related and directly essential thereto, 56 whether employed by the same or a different employee. (See §§ 776.17 to 776.19.) Typically, but not exclusively, this includes that large group of employees engaged in mines, oil fields, quarries, and manufacturing, processing, or distributing plants where goods are produced for commerce. The employees covered as engaged in “production” are not limited, however, to those engaged in actual physical work on the product itself or to those in the factories, mines, warehouses, or other place of employment where goods intended for commerce are being produced. If the requisite relationship to production of such goods is present, an employee is covered, regardless of whether his work brings him into actual contact with such goods or into the establishments where they are produced, and even though his employer may be someone other than the producer of the goods for commerce. 57 As explained more fully in the sections following, the Act's “production” coverage embraces many employees who serve productive enterprises in capacities which do not involve working directly on goods produced but which are nevertheless closely related and directly essential to successful operations in producing goods for interstate or foreign commerce. And as a general rule, in conformity with the provisions of the Act quoted in paragraph (a) of this section, an employee will be considered to be within the general coverage of the wage and hours provisions if he is working in a place of employment where goods sold or shipped in interstate commerce or foreign commerce are being produced, unless the employer maintains the burden of establishing that the employee's functions are so definitely segregated from such production that they should not be regarded as closely related and directly essential thereto. 58