Mo. Rev. Stat. § 341.010
Current with changes from the 2024 Legislative Session
That any person now or hereafter engaging or working at the business of plumbing in cities or towns of fifteen thousand or more inhabitants in this state, either as master plumber or journeyman plumber, shall first receive a certificate thereof in accordance with the provisions of sections 341.010 to 341.080.
§ 341.010, RSMo