ISO 20048-2:2023

ISO 20048-2:2023 - Overview

ISO 20048-2:2023 specifies an operational screening method to assess carbon monoxide (CO) off-gassing from solid biofuel pellets. Intended for preliminary operational planning, the standard defines sampling, sample handling and a reproducible laboratory procedure to measure CO emission trends (and support understanding of oxygen depletion risk) from pelletized biofuels stored in confined spaces. Results are for screening purposes and should be interpreted with the guidance and limitations given in the document.

Key topics and technical requirements

• Scope: Screening method for CO off-gassing from pelletized solid biofuels; guidance on applicability and use of data.
• Sampling & sample mass: Follow ISO 18135 or ISO 21945. Minimum test sample mass: 1 500 g (allows replication). Sample preparation per ISO 14780.
• Sample containers: Glass cylindrical containers, nominal 1 L (actual volume limited to 1 045 ml – 1 130 ml); containers without a neck; test portion fills containers to 75% of volume. CO data logger placed inside bulk must not reduce container volume by more than 5%.
• Temperature & apparatus: Heating apparatus (incubator/oven) with fan and insulation maintained at 40 °C ± 1 °C; perforated elevated floor for even heating. Preheat until stable for at least 10 min.
• CO measurement: Use CO data loggers (range 0–1000 ppm) capable of recording at least every 5 min; minimum two identical loggers per sample type (reproducibility and backup). Measure CO for at least 3 h (CO_max-3h recorded), up to 10 h where possible; longer tests give better accuracy but 3 h provides a reliable screening trend.
• Sample handling & storage: Prefer immediate testing; if transported, use airtight filled containers, avoid elevated temperatures. Short-term fridge storage 0–5 °C; freezing on receipt can allow 2–3 months storage without significant reactivity change (informative notes).
• Equipment accuracy: Laboratory balance accuracy to 0.1% of sample mass. Calibration of instruments and test reporting requirements are specified.

Practical applications and users

• Who uses it: Pellet manufacturers, storage and logistics operators, safety managers, occupational health teams, testing laboratories, insurers and regulators.
• Practical uses:
  • Rapid screening to identify batches with elevated CO off-gassing potential.
  • Operational planning for safe storage, ventilation needs and worker safety measures.
  • Pre‑selection of materials for more detailed analysis (see ISO/TS 20048‑1 for full emission/depletion measurement).

Related standards

• ISO 14780 - Solid biofuels - Sample preparation
• ISO 18135 - Solid biofuels - Sampling
• ISO 21945 - Simplified sampling for small scale applications
• ISO/TS 20048‑1 - (Related part in the ISO 20048 series for detailed emission and depletion rates)

Keywords: ISO 20048-2:2023, solid biofuels, carbon monoxide off-gassing, oxygen depletion, pellet screening method, sampling, CO data logger, pellet safety.