Maryland Code, Business Occupations and Professions § 12-605.2

(a) A person engaged in the business of selling plumbing supplies in the State may not sell pipes, pipe fittings, plumbing fittings, or fixtures that will be used in the installation or repair of any plumbing that dispenses water for human consumption, unless the pipes, pipe fittings, plumbing fittings, or fixtures are lead-free.

(b) A person engaged in the business of selling plumbing supplies in the State may not sell solder or flux that is not lead-free unless the solder or flux bears a label stating that it is illegal to use the solder or flux in the installation or repair of any plumbing that dispenses water for human consumption.