29 CFR 784.127: Office and clerical employees under section 13(a)(5).

Office and clerical employees, such as bookkeepers, stenographers, typists, and others who perform general office work of a firm engaged in operating fishing boats are not for that reason within the section 13(a)(5) exemption. Under the principles stated in § 784.106, their general office activities are not a part of any of the named operations even when they are selling, taking, and putting up orders, on recording sales, taking cash or making telephone connections for customer or dealer calls. Employment in the specific activities enumerated in the preceding sentence would ordinarily, however, be exempt under section 13(b)(4) since such activities constitute “marketing” or “distributing” within the meaning of that exemption (see § 784.153). In certain circumstances, office or clerical employees may come within the section 13(a)(5) exemption. If, for example, it is necessary to the conduct of the fishing operations that such employees accompany a fishing expedition to the fishing grounds to perform certain work required there in connection with the catch, their employment under such circumstances may, as a practical matter, be directly and necessarily a part of the operations for which exemption was intended, in which event the exemption would apply to them.