D.C. Mun. Regs. tit. 24, r. 24-313
When a sidewalk cafe or the adjacent restaurant is occupied, no exit door shall be locked, bolted, or otherwise fastened or obstructed so that the door is unable to be opened from the inside.
Chairs and tables shall be arranged so as to provide for ready access by aisles to each exit doorway. All aisles shall conform to § 610 of the D.C. Building Code.
No part of any aisle shall be used in any way that will obstruct its use as an exit or that will constitute a hazardous condition.
All fire protection equipment shall be kept in working condition. Extinguishers, hoses, and other fire protection appliances required by the Fire Chief shall be visible and convenient at all times.
All exits in an enclosed sidewalk cafe shall be marked and lighted in accordance with the D.C. Building Code and the D.C. Electrical Code.
D.C. Mun. Regs. tit. 24, r. 24-313