SIST EN ISO 21945:2020 PDF

Overview

EN ISO 21945:2020 (ISO 21945:2020) specifies a simplified sampling method for solid biofuels intended for small-scale applications and storages (main focus on storages ≤ 100 t). The standard covers practical procedures for taking representative samples, preparing sampling plans and reports, reducing sample size, and requirements for handling and storage. It is endorsed by CEN as EN ISO 21945:2020 and is intended to support reliable quality testing and fair trading of biofuels.

Key topics and technical requirements

• Scope of materials - Applies to:
  • Fine, regularly-shaped particulate materials (up to ≈10 mm) sampled by scoop or pipe (e.g., sawdust, wood pellets).
  • Coarse/irregular particulate materials (up to 200 mm) sampled by fork or shovel (e.g., wood chips, nut shells).
  • Large pieces (>200 mm) sampled manually (e.g., firewood, briquettes).
• Sampling planning and reporting - Guidance to prepare a sampling plan and a standardised sampling report; Annex A provides a model plan/report.
• Sampling methods - Procedures for stationary materials (small packages, transport containers, small built-in storages, stockpiles) and for moving materials (falling streams, conveyor belts, grabs, wheel loader buckets).
• Increment and combined sample rules - Minimum number and size of increments, and how to determine combined sample volume for analysis.
• Equipment - Recommended manual sampling tools (scoops, pipes/spears, sampling buckets, shovels, forks, drills/augers) and safe handling practices.
• Sample reduction and preparation - Methods for reducing sample size prior to laboratory tests, in line with ISO 14780 for sample preparation.
• Handling, storage and labelling - Packaging, identification and transport requirements to preserve sample integrity.
• Safety note - Pellets can emit CO and CO2 in confined spaces; the standard advises checking CO, CO2 and O2 levels and using an attendant when sampling in containers/silos.

Applications and users

• Practical uses:
  • Quality control and compliance testing (moisture content, ash content, calorific value, bulk density, mechanical durability, particle size distribution, ash melting behaviour, chemical composition).
  • Commercial trading and dispute resolution between sellers and buyers.
  • On-site sampling at small boilers, pellet stores, chip yards, delivery trucks and small storages.
• Intended users:
  • Biofuel suppliers and traders, heating plant operators, laboratory personnel, inspectors, equipment manufacturers and auditors.

Related standards

• ISO 18135 - Use when higher precision is required; formulas in ISO 18135 can estimate precision based on increments.
• ISO 14780 - Sample preparation for solid biofuels (normative reference).
• ISO 16559 - Terminology and definitions for solid biofuels.

Keywords: EN ISO 21945:2020, ISO 21945:2020, solid biofuels sampling, small scale sampling, pellet sampling, wood chip sampling, sampling plan, moisture testing, ash content.