Md. Code, Pub. Safety § 10-204

(a) (1) Subject to paragraphs (2) and (3) of this subsection, a mixing building or storage building of a fireworks plant shall be located at least: (i) 1,000 feet from a school, church, hospital, place of public assembly, or gasoline or fuel oil storage building or service station; and (ii) 200 feet from any other inhabited building, a highway, or a railroad. (2) A building within a fireworks plant that contains hazardous mixes or items may not be located nearer to the fireworks plant property line than is authorized under regulations adopted by the State Fire Prevention Commission. (3) (i) Except as provided in subparagraph (ii) of this paragraph, a finishing and assembling building shall be located at least: 1. 75 feet from any other finishing and assembling building; and 2. 200 feet from any storage building used primarily to store finished fireworks other than sparklers. (ii) If a candle building or rocket press building of a fireworks plant is constructed of approved fire-resistant materials, is barricaded, and otherwise meets the requirements of the State Fire Prevention Commission, the building shall be located at least 50 feet from other finishing and assembling buildings. (4) A licensee may package and repackage 1.4 G fireworks in finished form in a storage building if there is a minimum separation distance of 25 feet between the packaging area and any stored fireworks. (5) Except as provided under paragraph (3)(ii) of this subsection, a distance prescribed under this section may not be reduced because of the presence of a barricade or earth cover. (b) (1) Except as provided in paragraph (2) of this subsection, a fireworks plant shall be completely surrounded by a substantial fence that: (i) is at least 6 feet tall; (ii) contains at least three strands of barbed wire; and (iii) except as provided in paragraph (3) of this subsection, contains openings equipped with suitable gates that are kept securely locked when not in use. (2) Except for an office building in which processing or storage is prohibited, each building in a fireworks plant shall be located within the fence required under paragraph (1) of this subsection. (3) The main gate of the plant may be left open during the regular hours of plant operation if the gate is within the unobstructed view and under the observation of authorized responsible employees or guards. (4) The licensee shall post conspicuous signs at least every 500 feet along the fence of the fireworks plant that state “WARNING - NO SMOKING - NO TRESPASSING”.