D.C. Mun. Regs. tit. 19, r. 19-2402
The fighting area canvas shall be no smaller than 18 feet by 18 feet and no larger than 32 feet by 32 feet. The fighting area canvas shall be padded in a manner as approved by the Commissioner, with at least one-inch layer of foam padding. Padding shall extend beyond the fighting area and over the edge of the platform. No vinyl or other plastic rubberized covering shall be permitted.
The fighting area canvas shall not be more than four feet above the floor of the building and shall have suitable steps or ramp for use by the participants. Posts shall be made of metal not more than six inches in diameter, extending from the floor of the building to a minimum height of 58 inches above the fighting area canvas and shall be properly padded in a manner approved by the Commissioner.
The fighting area canvas area shall be enclosed by a cage or fence made of such material as will not allow a fighter to fall out or break through it onto the floor or spectators, including, but not limited to, vinyl coated chain link fencing. All metal parts shall be covered and padded in a manner approved by the Commissioner and shall not be abrasive to the contestants.
The cage or fence shall provide two separate entries onto the fighting area canvas.
D.C. Mun. Regs. tit. 19, r. 19-2402