scope:

General

This Standard covers the design, fabrication, installation, inspection, testing, and the safety aspects of operation and maintenance of gas pipeline systems including gathering lines, transmission lines, compressor stations, metering and regulating stations, distribution lines, service lines, and offshore pipelines.

The scope of this Standard, which includes the following, is shown in Figure 1.1:

(a) Gas storage equipment of the closed pipe type fabricated or forged from pipe or fabricated from pipe and fittings, and gas storage lines; and

(b) The conditions of use of the elements of the pipeline systems described in Clause 1.1.1, including, but not limited to, pipe, valves, fittings, flanges, bolting. gaskets, regulators, pressure vessels, pulsation dampeners, and relief valves.

Note: Designers are cautioned that, while some sections apply to other gases, this Standard was prepared as a minimum standard for the design, construction, and operation of gas distribution and transmission systems as portrayed in Figure 1.1.

This Standard does not apply to:

(a) Design and fabrication of pressure vessels covered by appropriate pressure vessel codes;

(b) Piping with metal temperatures above 230°C or below -70°C;

(c) Piping beyond the termination of the utility installation*;

*For such piping see CGA Standard CAN1-B149.1, Installation Code for Natural Gas Burning Appliances and Equipment.

(d) Piping in oil refineries, natural gasoline extraction plants, gas treatment plants (except main gas stream piping in dehydration and all other processing plants installed as part of a gas pipeline system), gas manufacturing plants, industrial plants, or mines;

(e) Vent piping to operate at substantially atmospheric pressures for waste gases of any kind;

(f) Wellhead assemblies, including control valves or casing and tubing in gas or oil wells;,

(g) Proprietary items of equipment, apparatus, or instruments;

(h) Heat exchangers;

(i) Oil or liquid products pipelines;

(j) Prefabricated units that employ plate and longitudinal welds as contrasted to pipe; and

(k) Liquefied natural gas pipelines.

It is not intended that the application of this Standard shall prevent the development of new equipment or practices, nor to prescribe specifically how such innovations should be handled.

Where any requirements of this Standard are at variance with the requirements of other standards or codes incorporated by reference into this ,Standard,.the requirements of this Standard shall govern.

It is not intended that the requirements of this Standard be applied retroactively to existing installations insofar as design, fabrication, installation, established operating pressure and testing are concerned. lt is intended, however, that the provisions of this Standard shall be applicable to the operation, maintenance, and upgrading of existing installations.

This Standard is intended to establish essential requirements and minimum standards for the design, installation, and operation of gas pipeline systems. It is not a design handbook and the need for exercising competent engineering judgement is a necessary requirement to be employed concurrently with its use.

The term "shall" as used in this Standard indicates a mandatory requirement. The term "should" indicates a recommended practice.