CGA G-1.2-2019 PDF

Full title and description

St CGA G-1.2-2019 — Standard for Acetylene Metering and Piping. This CGA standard (G‑1.2, 5th edition) compiles recommended practices for the metering, pipeline transmission and user‑site piping of acetylene, with guidance that addresses the gas properties, metering techniques for large and small volume meters, piping components, and special precautions required because of acetylene’s instability.

Abstract

CGA G‑1.2‑2019 is organized in three main parts: (1) properties of acetylene, (2) pipeline acetylene transmission (metering and related considerations), and (3) acetylene piping (components, construction and operation). The publication compiles experimental and field‑proven practices relevant to safe metering and transmission of dissolved acetylene and includes discussion of metering recommendations (large‑ and small‑volume meters), piping system components, and the general explosive behavior of acetylene in piping systems with attendant protective measures. The scope is limited to acetylene at specified purity and pressure limits.

General information

• Status: Current (active CGA standard; 2019 edition in use as the G‑1.2 reference).
• Publication date: 17 December 2019 (published as the 2019 edition).
• Publisher: Compressed Gas Association (CGA).
• ICS / categories: Industrial gases; piping and pipeline safety; gas metering and measurement (general classification: acetylene, gas handling, piping systems).
• Edition / version: 5th edition (G‑1.2, 2019).
• Number of pages: 48 pages (CGA product listing; some reseller listings show alternate page counts).

Scope

The standard’s scope is limited to acetylene service up to a maximum working pressure of 400 psi (≈ 2,760 kPa) and addresses acetylene of high purity (greater than 99.5% on a dry basis). It provides recommended practices for metering (sections covering both large‑ and small‑volume meters), guidelines for pipeline transmission, and requirements and recommendations for piping components and installation at user locations. The document emphasizes special construction and operational precautions required because of acetylene’s instability and potential for explosive decomposition in certain piping conditions.

Key topics and requirements

• Physical and chemical properties of acetylene relevant to metering, piping and safety (including recommended standard conditions).
• Recommendations and accepted practices for metering acetylene (large and small volume meters; metering sections typically noted in the standard).
• Pipeline transmission practices for dissolved acetylene, including pressure limits and flow considerations.
• Design, materials, and component recommendations for acetylene piping systems (valves, fittings, joints, prohibited materials and special material considerations).
• Guidance on the explosive behavior of acetylene in piping and required protective measures and operational controls.
• Limitations on gas composition (purity >99.5% dry basis) and the exclusion of acetylene mixtures from the scope unless specifically addressed.

Typical use and users

Primary users include gas producers and suppliers, pipeline and trailer operators, plant/process engineers, measurement and instrumentation specialists, safety and compliance personnel, and authorities having jurisdiction responsible for acetylene handling and distribution. The standard is used to develop safe metering installations, design piping systems for acetylene service, and support regulatory and operational compliance for acetylene handling.

Related standards

Related CGA publications commonly referenced alongside G‑1.2 include CGA G‑1 (Acetylene), CGA G‑1.1 (Commodity Specification for Acetylene), other G‑series acetylene guidance (for example G‑1.6 for mobile acetylene tank systems where applicable), and pressure relief device standards such as CGA S‑1.1 and S‑1.2. Regulatory guidance from agencies (e.g., PHMSA/OSHA) often references CGA documents for transportation and handling requirements.

Keywords

acetylene; acetylene metering; acetylene piping; pipeline transmission; gas metering; CGA G‑1.2; dissolved acetylene; piping safety; explosive decomposition; industrial gases.

FAQ

Q: What is this standard?

A: CGA G‑1.2‑2019 is the Compressed Gas Association’s Standard for Acetylene Metering and Piping (5th edition), providing recommended practices for safe metering, transmission and piping of acetylene.

Q: What does it cover?

A: It covers acetylene properties, metering recommendations (large and small meters), pipeline transmission practices, piping components and installation, and the general explosive behaviour of acetylene with associated protective measures. The scope is limited to acetylene up to 400 psi and to high‑purity acetylene (greater than 99.5% on a dry basis).

Q: Who typically uses it?

A: Gas suppliers, distribution and pipeline operators, plant/process engineers, instrumentation and metering specialists, safety/compliance officers, and regulators—any organization involved in the metering, transmission or piping of acetylene.

Q: Is it current or superseded?

A: The 2019 edition (G‑1.2‑2019, 5th edition) is the active CGA edition published in December 2019 and supersedes previous editions (for example the 2012 edition). Users should verify whether a newer revision has been published before relying on the standard for regulatory incorporation.

Q: Is it part of a series?

A: Yes — G‑1.2 is part of the CGA G‑series publications on acetylene and related guidance documents (G‑1, G‑1.1, G‑1.6, etc.), and it is intended to be used in conjunction with other CGA and regulatory publications that address cylinders, pressure relief devices and transport/handling.

Q: What are the key keywords?

A: Acetylene, metering, piping, pipeline transmission, dissolved acetylene, CGA G‑1.2, gas metering, explosive behaviour, pressure limits (400 psi), high‑purity acetylene.