Over time, this has led to some overlap in current standards, while some standards have a lack of detail in areas such as welding on steel gas mains and on aspects of maintenance. In addition, there is an indiscriminate mix of both prescriptive and performance requirements in the majority of the existing standards.

The plastics section of the gas distribution standards is quite outdated, with the main revision completed 18 years ago. A reader could be left with the impression that AS3723 - Installation and maintenance of plastics pipe systems for gas when referred to in AS4645 - Gas distribution network management is intended to apply for plastic systems up to 1,050 kPa. The engineering controls required for operation at such pressure are not encompassed in the current AS3723.

AS2885 - Pipelines - Gas and liquid petroleum has led the way in terms of developing an integrated suite of standards that deals with gas transmission issues. Now, the industry, through Standards Australia Committee AG-008 - Gas Distribution, is attempting to integrate gas distribution standards into one easy to use structure.

The standards affected are:

AS4645 Gas distribution network management.

AS1697 Installation and maintenance of steel pipe systems for gas.

AS3723 Installation and maintenance of plastics pipe systems for gas.

AS4568 Preparation of a safety and operating plan for gas networks.

One of the objectives of the Standards Australia Committee AG-008 is to separate performance and prescriptive requirements in the standards as much as possible and provide a stand alone performance-based standard.

Separating these requirements will allow businesses flexibility in how to achieve the required outcomes of the standard, as well as providing the opportunity for innovation and efficiencies within the Gas Distribution Standard framework and the relevant Key Performance Indicators (KPIs). The standard sets out KPIs which allow a more universal best practice assessment to take place.

Concurrently, there is a need to consolidate the prescriptive requirements of the standards and provide a ‘deemed to comply’ solution that gives detailed guidance on how to achieve the desired safety outcomes. The prescriptive sections for steel networks (Part Three) may suit smaller systems as a means of compliance without extensive risk assessments and proving of performance.

These standards will be bought together in a new three part structure with a common numbering system. Part One will deal with performance requirements of network management and Parts Two and Three will deal with ‘deemed to comply’ solutions for both steel and plastic pipe systems respectively.

An exposure draft of the Gas Distribution Standard could possibly be completed by the end of the year.