D.C. Mun. Regs. tit. 18, r. 18-1204
Each bicycle shall be equipped with a brake which enables the operator to cause the braked wheels to skid on dry, level, clean pavement; provided, that a fixed gear bicycle is not required to have a separate brake, but an operator of a fixed gear bicycle shall be able to stop the bicycle using the pedals.
Each bicycle, when in use at night, shall be equipped with a lamp on the front which shall emit a steady or flashing white light visible from a distance of at least five hundred feet (500 ft.) to the front and with a red reflector on the rear which shall be visible from all distances from fifty feet (50 ft.) to three hundred feet (300 ft.) to the rear when directly in front of upper beams of head lamps on a motor vehicle.
A lamp emitting a steady or flashing red light visible from a distance of five hundred feet (500 ft.) to the rear may be used in lieu of the red reflector.
In place of the requirements of § 1204.2, a lamp may be worn on the body of an operator; provided, that it may be readily seen from the distances set forth in that subsection.
A bicyclist riding within the District must be capable of making a warning noise, either with a bell or mechanical device, or with his or her voice, audible for a distance of at least one hundred feet (100 ft).
A bicycle shall not be equipped with, nor shall any bicycle rider use, a siren of any kind.
[REPEALED]
D.C. Mun. Regs. tit. 18, r. 18-1204