D.C. Mun. Regs. tit. 25, r. 25-D801
Except as specified in section 805, the floors, floor coverings, walls, wall coverings, and ceilings shall be designed, constructed, and installed so they are smooth and easily cleanable, except that antislip floor coverings or applications may be used for safety reasons.
The floors in massage therapy rooms, on-site laundry areas, food staging or serving areas, in bathrooms, locker rooms, and toilet rooms, which are next to spas, whirlpool therapy tubs, bathtubs, showers or toilets, or any other wet areas shall be constructed of smooth, durable, nonabsorbent and easily cleanable material.
Every concrete, tile, ceramic and vinyl floor installed in an on-site laundry area, food areas, and areas in bathrooms, restrooms, locker rooms, and toilet rooms, which are next to spas, whirlpool therapy tubs, bathtubs, showers or toilets shall be coved at the junctures between the floor and the walls.
All material used to cove the junctures shall be fitted snugly to the floor and the walls so that they are water tight and there are not openings large enough to permit the entrance of vermin.
Exposed utility service lines and pipes shall be installed so they do not obstruct or prevent cleaning of the floors, walls, or ceilings.
Exposed horizontal utility service lines and pipes shall not be installed on the floor and utility service lines and pipes shall not be unnecessarily exposed.
The material used in constructing the walls and ceilings must be joined along their edges so as to leave no open spaces or cracks.
Massage therapy room shall be constructed and maintained to provide client privacy; and locks or devices that prevent easy entry or exit shall not be permitted on any door.
D.C. Mun. Regs. tit. 25, r. 25-D801