5303.2.3 Piping systems.
FC § 5303.2.3
Piping systems shall be marked in accordance with ASME A13.1. Markings used for piping systems shall consist of the name of the contents and include an arrow indicating direction of flow. Markings shall be provided at each valve; at wall, floor or ceiling penetrations; at each change of direction; and at a minimum of every 20 feet (6096 mm) or fraction thereof throughout the piping run. Exceptions: 1. Piping that is designed or intended to carry more than one compressed gas at various times shall have appropriate signs or markings posted at the manifold, along the piping and at each point of use to provide clear identification and warning.
2.Piping within gas-manufacturing plants, gas-processing plants and similar occupancies shall be marked in an approved manner.
