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From Maryland DNR Site
Forest Fire Protection The Maryland Forest Service enforces open air burning regulations. The following regulations apply to activities in woodland, and within 200 feet of woodland, or activities adjacent to or within an area where flammable materials, that could ignite and carry fire to woodland, are located. These regulations do not apply in incorporated towns or to small recreational fires such as campfires.
Open Air Burning Regulations
A person may not engage in open air burning without permit. The following conditions apply:
1. There is a natural or constructed fire break at least 10 feet wide completely around the material to be burned that is free of flammable materials;
2. Adequate personnel and equipment are present to prevent the fire from escaping;
3. At least one responsible person remains at the location of the fire until the last spark is out; and
4. Burning occurs between the hours of 4:00 pm and 12:00 midnight EST, except when the ground is covered with snow the burning may occur at any time so long as all other requirements are met.
In addition to the requirements of this regulation, a person engaged in open air burning shall comply with all other requirements of other state and local jurisdictions.
To obtain a Maryland DNR Forest Service Open Air Burning permit contact your local Forest Service Office.