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Subchapter 1. Unfired Pressure Vessel Safety Orders
Article 7. Compressed and Liquefied Natural Gas System

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515. Systems Utilizing Portable DOT NH 3 Containers.

(a) Cylinders shall comply with DOT specifications and shall be maintained, filled, packaged, marked, labeled, and shipped to comply with 49 CFR Chapter 1 and Marking Portable Compressed Gas Containers to Identify the Material Contained, ANSI Z48.1-1954 (R1970).

(b) Cylinders shall be stored in an area free from ignitable debris and in such manner as to prevent external corrosion. Storage may be indoors or outdoors.

(c) Cylinders filled in accordance with DOT regulations will become liquid full at 145o F. Cylinders shall be protected from heat sources such as radiant flame and steampipes. Heat shall not be applied directly to cylinders to raise the pressure.

(d) Cylinders shall be stored in such manner as to protect them from moving vehicles or external damage.

(e) Any cylinder which is designed to have a valve protection cap shall have the cap securely in place when the cylinder is not in service.


*For Appendix A, refer to end of Subchapter 1.

The provisions of Article 7 apply to the storage, dispensing and use of natural gas as a motor fuel except in vehicles that are licensed to travel on highways, for which the standards of the California Highway Patrol apply.

Authority cited: Section 142.3, Labor Code.



1. New section filed 3-28-75; effective thirtieth day thereafter (Register 75, No. 13).

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