Md. Code, Tax - Property § 7–240

Personal property is not subject to property tax if the property:

(1) is owned by a nonprofit organization that:

(i) is qualified as tax exempt under § 501(c)(4) of the Internal Revenue Code; and

(ii) is engaged primarily in providing a program to render its best efforts to contain, clean up, and otherwise mitigate spills of oil or other substances occurring in United States coastal and tidal waters; and

(2) is used for the purposes of the organization.