Md. Code, Public Safety § 14–503

(a) The Program applies to:

(1) motor gasoline;

(2) middle distillate;

(3) propane;

(4) residual fuel oil, except as provided in subsection (b) of this section; and

(5) aviation gasoline.

(b) The Program does not apply to residual fuel oil that is used:

(1) in an electric generating station; or

(2) as bunker fuel for marine shipping.