D.C. Mun. Regs. tit. 25-C, § 6425
6425.1 The equipment enclosure, area or room floor shall be of concrete or other nonabsorbent material having a smooth slip resistant finish and shall have positive drainage, including a sump pump if necessary.
6425.2 Ancillary equipment, such as a heater, not contained in an equipment enclosure or room shall necessitate an equipment area as specified in section - 6424.1.
SOURCE: Final Rulemaking published at 55 DCR 012845 (December 26, 2008).