Section 520.401 - Are there any industries, occupations, etc. that do not qualify for a certificate to employ messengers, learners, or apprentices at subminimum wages?(a) Certificates to employ messengers at subminimum wages are available to only those establishments engaged in the business of providing messenger service, i.e., the delivery of letters and messages. Requests for such certificates are uniformly denied to applicants whose principal business purpose is not the delivery of messages and letters.(b) All applications for special certificates authorizing the employment of learners at subminimum wage rates in the manufacture of products in the following industries shall be denied (definitions for all listed activities can be found in subpart C of this part):(1) In the apparel industry: (ii) Leather and sheep-lined clothing(iii) Women's apparel division of the apparel industry for the manufacture of women's misses', and juniors' dresses;(2) Shoe manufacturing industry(3) Men's and boys' clothing industry.(c) No certificates will be granted authorizing the employment of learners at subminimum wage rates as homeworkers; in maintenance occupations such as guard, porter, or custodian; in office and clerical occupations in any industry; or in operations of a temporary or sporadic nature.(d) Authorization to employ apprentices at subminimum wages will only be granted if permitted by the BAT regulations ( 29 CFR Part 29 ).