California Code of Regulations
Title 8 - Industrial Relations
Division 1 - Department of Industrial Relations
Chapter 4 - Division of Industrial Safety
Subchapter 1 - Unfired Pressure Vessel Safety Orders
Article 7 - Compressed and Liquefied Natural Gas System
Section 538 - Hose, Metallic Hose, Flexible Metal Hose and Tubing Specifications

(a) Hose and metallic hose shall be of or lined with materials that are resistant to corrosion and to the actions of natural gas.

(b) Hose, metallic hose, flexible metal hose and tubing shall be suitable for the most severe pressure and temperature service conditions expected with a burst pressure of at least 4 times the maximum working pressure. Flexible metal hose or pipe with swivel joints shall be used for transfer operations where operating temperatures during transfer will be less than minus 20 degrees Fahrenheit.

(c) Connections for hose, metallic hose, flexible metal hose and tubing shall be designed with a burst pressure of at least 4 times the most severe pressure and temperature conditions expected.

(d) The components of the hose and metallic hose shall be tested after assembly and prior to use to at least 2 times the service pressure, and also tested to a pneumatic pressure of at least 600 psi under water. After the original installation, all hoses shall be examined visually at such intervals as are necessary to assure that they are safe for use. In no case shall such examination interval exceed one year. Hose shall be tested for leaks with soap suds or equivalent at least annually and any leakage shall be reason for rejection. This test shall be recorded and the record shall be available to the qualified inspector.

(e) All hose, metallic hose, flexible metal hose and tubing and their connections shall be maintained in a safe condition.

(f) While in transit, all hose and flexible metal hose and tubing to be used in the transfer operation, including their connections, shall be protected from wear or injury and shall be capped.

(g) Hose, metallic hose, flexible metal hose and tubing shall be distinctly marked either by the manufacturer's permanently attached tag or by distinct markings every 5 feet indicating the manufacturer's name or trademark, service and working pressure.