Regulationcurrent
49 CFR 192.189
Vaults: Drainage and waterproofing.
Current as of 2026-08-18 Government source
eCFR editorial compilationAuthoritative but unofficial
View source (a)Each vault must be designed so as to minimize the entrance of water.#
(b)A vault containing gas piping may not be connected by means of a drain connection to any other underground structure.#
(c)Electrical equipment in vaults must conform to the applicable requirements of Class 1, Group D, of the National Electrical Code, NFPA-70 (incorporated by reference, see § 192.7).#