ISO/TR 7262:2022

Overview

ISO/TR 7262:2022 is a Technical Report from ISO/TC 193 that surveys global practices for coalbed methane (CBM) quality designation and assesses whether existing ISO/TC 193 standards for sampling, testing and calculation are applicable to CBM. The document clarifies terms and definitions, lists symbols and units, and evaluates standards for gas composition, physical properties, dew points, particulate matter and sulfur content. It aims to support consistent communication, exploration, production and custody transfer of unconventional natural gas.

Key topics and technical requirements

• Scope and references: Links to ISO 14532 (vocabulary) and ISO 18875 (CBM terms and definitions).
• Sampling applicability: Confirms ISO 10715 is applicable for direct and indirect sampling of CBM, covering sampling strategy, probe location, equipment and sample handling.
• Gas composition ranges (typical CBM, from the report):
  • Methane: 50–99 mol%
  • Ethane: 0.1–5 mol%
  • Propane, butanes, pentanes: trace to small mol% ranges
  • Nitrogen: 0.1–40 mol%
  • Carbon dioxide: 0.1–15 mol%
  • Hydrogen, oxygen, CO, noble gases and sulfur species at low concentrations; total sulfur and H2S reported as 0–20 mg/m3.
• Applicability of ISO/TC 193 test standards: Assessment of GC and calculation standards (ISO 6974 series, ISO 23978, ISO 6975, ISO 6976) for major, minor and trace components. Methane, ethane, propane and C4–C5 components are generally covered; applicability to nitrogen and CO2 may be limited in some cases (“not exactly” as indicated).
• Gas properties and calculations: Evaluation of calorific value (mass/volumetric), relative density, Wobbe index, compression factor, and density calculation methods.
• Dew points and condensables: Water dew point, hydrogen dew point / hydrocarbon dew point (HCDP), and potential hydrocarbon liquid content (PHLC).
• Particulate matter: Considerations and technical notes on solids in CBM (see Annex B). Annex A summarizes technical requirements and test methods for CBM.

Applications and users

ISO/TR 7262:2022 is valuable for:

• CBM explorers and producers planning development and custody transfer
• Analytical laboratories and gas chemists validating methods for CBM samples
• Pipeline and distribution operators assessing interconnection quality limits
• Regulators and standards bodies harmonizing CBM quality designations
• Procurement, metering and QA/QC engineers managing gas specifications

Related standards

• ISO 10715 - Sampling of natural gas streams
• ISO 6974 (series), ISO 23978 - Gas chromatography and component analysis
• ISO 6975, ISO 6976 - Calculation of properties (calorific value, Wobbe, density)
• ISO 14532, ISO 18875 - Vocabulary and CBM terminology

Keywords: ISO/TR 7262:2022, coalbed methane, CBM quality, natural gas standards, sampling, gas analysis, calorific value, Wobbe index, dew point, ISO/TC 193.