N.Y.C. Admin. Code § FC 3509: Section FC 3509: Piping Manifolds and Hose Systems for Fuel Gases and Oxygen

3509.1 General.

The use of piping manifolds, protective equipment and hose systems in oxygen-fuel gas systems, including natural gas supplied from a utility for use in an oxygen-fuel gas system, shall be designed, installed, operated and maintained in accordance with FC 3509, FC Chapter 53 and NFPA 51.

3509.2 Protection.

Piping shall be protected against physical damage.

3509.3 Signage.

Signage shall be provided for piping and hose systems as follows:

1. Aboveground piping systems shall be marked in accordance with ASME A13.1.

2. Station outlets shall be marked to indicate their intended usage.

3. Signs shall be posted, indicating clearly the location and identity of section shutoff valves.

3509.4 Manifolding of containers.

Oxygen manifolds shall be located at least 20 feet (6096 mm) away from combustible waste and combustible material, including oil and grease, and gas containers containing flammable gases, unless the gas containers are separated from each other by a fire partition.

3509.5 Identification of manifolds.

Signs shall be posted for oxygen manifolds with service pressures not exceeding 250 psig (1379 kPa). Such signs shall read as follows:

LOW-PRESSURE MANIFOLD DO NOT CONNECT HIGH-PRESSURE CONTAINERS MAXIMUM PRESSURE 250 PSIG

3509.6 Clamps.

Hose connections shall be clamped or otherwise securely fastened.

3509.7 Inspection.

Hoses shall be inspected frequently for leaks, burns, wear, loose connections or other defects.

3509.8 Piped natural gas precautions.

When piped natural gas is used with oxygen in any hot work operation, a listed protective device that serves as a combination flashback arrester and backflow check valve shall be provided at an approved location on both the natural gas and oxygen supply lines so as to ensure the safe operation of all devices, equipment and systems, including the utility gas meter. Where pressure of the piped natural gas supply is insufficient to ensure such safe operation, approved equipment shall be provided between the gas meter and the fuel-consuming appliance that increases such pressure to the level required for such safe operation. Notwithstanding any section of this code to the contrary, such flashback arresters and check valves, pressure-increasing equipment, shall be installed as components of both new and existing installations. Installations involving the use of piped natural gas with oxygen in any hot work operation shall additionally comply with the rules.