(a) A messenger certificate, if issued, shall specify:

(1) The subminimum wage rate of not less than 95 percent of the applicable minimum wage required by section 6(a) of the FLSA; and

(2) The effective and expiration dates of the certificate.

(b) The employer shall post a copy of the messenger certificate during its effective period in a conspicuous place where it can be readily seen by employees.

(c) No messenger shall be hired under a messenger certificate while abnormal labor conditions such as a strike, lock-out, or other similar condition, exist.