34 Pa. Code § 14a.57
Piping systems shall contain a sufficient number of valves to operate the system properly and to protect the plant. Piping systems in connection with pumps shall contain a sufficient number of valves to control properly the flow of liquid in normal operation and in the event of physical damage. Each connection to piping by which equipment such as tank cars, tank vehicles or marine vessels discharge liquids into storage tanks shall be provided with a check valve for automatic protection against back-flow if the piping arrangement is such that back-flow from the system is possible.
The provisions of this § 13.57 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131; transferred from 37 Pa. Code and renumbered as 34 Pa. Code § 14a.57, February 28, 2014, effective March 1, 2014, 44 Pa.B. 1233. Immediately preceding text appears at serial page (259938).
This section cited in 34 Pa. Code § 14a.8 (relating to vents); 34 Pa. Code § 14a.51 (relating to scope and application); 34 Pa. Code § 14a.52 (relating to general design specifications); and 34 Pa. Code § 14a.161 (relating to general provisions).