ISO 6338-1:2024

Overview

ISO 6338-1:2024 - Calculations of greenhouse gas (GHG) emissions throughout the liquefied natural gas (LNG) chain - Part 1: General provides a standardized, auditable framework to quantify and report the carbon footprint of the LNG industry. This part sets out the general principles, boundaries and methods for calculating GHG emissions across facilities “under operation” (including start‑up, maintenance and restarts), and covers emissions across Scope 1, Scope 2 and Scope 3 as defined in the standard.

Key features:

• Framework for measuring and estimating emissions across the LNG chain
• Definitions of preferred units and conversion methods
• Guidance on instrumentation, estimation, allocation and reporting
• Coverage of all emission sources: flaring, combustion, cold/process vents, fugitive leaks, imported energy

Key Topics and Technical Requirements

• Principles for GHG inventories: relevance, completeness, consistency, transparency, accuracy and conservativeness.
• Inventory boundaries: what operational phases are included (operations, maintenance) and which are excluded (construction, commissioning, decommissioning).
• Source identification & quantification: methods for fuel combustion, flaring/venting, fugitive emissions, and emissions from imported energy, utilities and consumables.
• Preferred units & conversion factors: recommended units and Annex A conversion guidance to ensure comparability.
• Allocation rules: how to allocate emissions when multiple products are produced (e.g., LNG, LPG, condensates, sulfur).
• Carbon capture: opportunities and methods to quantify captured carbon benefits.
• Quality management: uncertainty estimation, documentation/archiving, quality control and assurance, and requirements for independent review.
• Reporting: content and additional information for transparent GHG disclosure.

Practical Applications

• Establishing an auditable LNG carbon footprint for corporate sustainability reporting.
• Supporting regulatory compliance, investor due diligence and market claims for low‑emission LNG.
• Designing monitoring programs (instrumentation + estimation) and internal GHG reduction strategies.
• Allocating emissions among co‑products to support commercial contracts, offsets or carbon pricing mechanisms.
• Integrating with life cycle assessment (LCA) and corporate GHG inventories.

Who Should Use This Standard

• LNG operators, plant managers and sustainability teams
• Environmental and emissions engineers
• LCA practitioners and corporate GHG accountants
• Auditors, verifiers and regulators
• Investors and commercial teams assessing low‑carbon LNG supply chains

Related Standards

• ISO 14064‑1 (GHG quantification and reporting at organization level)
• ISO 14044 (Life cycle assessment)
• API Consistent Methodology for Estimating GHG Emissions from LNG Operations
• Other parts of the ISO 6338 series (specific chain segments)

ISO 6338-1:2024 is a practical, industry‑focused reference for consistent, transparent calculation and reporting of LNG‑chain GHG emissions and the resulting carbon footprint.