All walls, ceilings, doors, windows, skylights, other closures, fixtures and decorative material shall be kept clean and in good repair.
The walls of massage therapy rooms, bathrooms, restroom, locker rooms, toilet rooms, and food areas shall be smooth and easily cleanable.
In wet areas of the bathroom, the walls and ceilings shall be constructed of materials and have finishes that are resistant to water.
Except in areas used only for dry storage, concrete, porous blocks, or bricks used for indoor wall construction shall be finished and sealed to provide a smooth, nonabsorbent, easily cleanable surface.
D.C. Mun. Regs. tit. 25, r. 25-D806