ISO/TS 20048-1:2020 PDF

Overview

ISO/TS 20048-1:2020 specifies a laboratory method for measuring off-gassing (permanent gases) and oxygen depletion from solid biofuels in closed containers. The technical specification applies to woody and non‑woody biomass - including pellets, briquettes, chips, torrefied and carbonized materials - and uses gas chromatography (GC) to quantify gas species. Results are reported as emission and depletion factors and rates (g/kg and g/kg·day) and are intended to guide ventilation strategies to keep concentrations below Permissible Exposure Levels (PEL).

Key Topics and Requirements

• Scope: Laboratory determination of permanent gas emissions and oxygen consumption from densified and non‑densified solid biofuels.
• Measurement principle: Sealed test containers with controlled headspace (typically 25% of container volume) are incubated at controlled temperatures (examples: 20 °C, 30 °C, 40 °C, 50 °C). Gas samples are withdrawn via a septum and analyzed by GC.
• Output metrics: Emission factor, depletion factor, emission rate and depletion rate per gas species.
• Apparatus & sampling: Preferably glass containers, PTFE/neoprene seals, gas‑tight GC syringes, temperature‑controlled ovens and calibrated GC analyzers.
• Data use: Conversion of GC volume fractions (ppmv) to mass-based factors and estimation of required air exchanges for ventilated spaces (Annex B).
• Quality controls: Requirements for sample preparation, container filling (75% load typical), void fraction/porosity determination and GC quantification procedures (Annex A).

Applications and Users

Who benefits from ISO/TS 20048-1:2020:

• Testing laboratories performing standardized off‑gassing assays for solid biofuels.
• Fuel producers and pellet manufacturers assessing product storage safety and quality.
• Storage and logistics operators (silos, bulk storage) for risk assessment of enclosed atmospheres.
• Occupational hygienists and safety officers estimating ventilation to control exposures to carbon monoxide (CO) and other off‑gassing species and to mitigate oxygen depletion risks.
• Regulators and risk assessors establishing handling and storage guidance tied to PELs and explosion/toxicity prevention.

Practical uses include comparing biomass types, evaluating the impact of thermal treatment (torrefaction/carbonization), and deriving ventilation rates to prevent toxic or asphyxiating atmospheres.

Related Standards

ISO/TS 20048-1 references and complements other solid biofuel standards such as:

• ISO 16559 (terminology)
• ISO 18135 (sampling)
• ISO 14780 (sample preparation)
• ISO 18134‑1/2, ISO 17828, ISO 17827‑2, ISO 18846, ISO 18847

Keywords: ISO/TS 20048-1:2020, solid biofuels, off-gassing, oxygen depletion, gas chromatography, pellets, briquettes, emission factor, depletion rate, ventilation, PEL.