Overview
ISO 18400-106:2017 - "Soil quality - Sampling - Part 106: Quality control and quality assurance" provides clear guidance on quality assurance (QA) and quality control (QC) specifically for soil sampling. The standard identifies which steps of the sampling process require QA/QC, describes management of those steps, and gives guidance for applying QA/QC across the ISO 18400‑100 series (levels 1 and 2) while offering direction for level 3 methods. It is intended to ensure soil samples are “fit for purpose” and that results are reproducible and defensible.
Key topics and technical requirements
- Scope of QA/QC: Applies QA in both accredited/certified systems and on a voluntary basis; emphasizes that QA procedures must be appropriate to project objectives.
- Sampling process control: All steps in sampling (planning, taking samples, pretreatment, transport) should be subject to QA/QC and have clearly defined roles and responsibilities.
- Procedures and documentation: Project managers must define organizations, teams, procedures, and information exchanges; use standardized reporting forms/software and retain versioned records.
- Data and document management: Unique identifiers, archived records, and tracked document versions are required to maintain traceability.
- Personnel and safety: Minimum requirements for knowledge, experience and on-site safety are specified as part of QA.
- Equipment and calibration: Selection, calibration, servicing, and assessment of equipment influence on results are covered.
- Sampling and QC sample types: Guidance on taking routine samples and dedicated QC samples such as blind replicates, split samples, trip blanks and field blanks, plus evaluation of QC results.
- Preservation, storage and transport: Chain of custody and sample integrity measures are required to avoid contamination or alteration.
- Communication and audits: Project communication, audits, and responsibilities for changes in-field are part of the QA framework.
Practical applications and who uses it
ISO 18400-106 is used by:
- Environmental consultants and field sampling teams planning and executing soil investigations
- Project managers who must define sampling plans, QA/QC procedures and chain of custody
- Accredited laboratories and QA professionals verifying sample integrity and documentation
- Regulators, remediation contractors, and land managers requiring defensible, reproducible soil data
Practical benefits include improved sample representativeness, reduced cross‑contamination, auditable sample chains, and clearer assignment of responsibility when field conditions change.
Related standards
- ISO 18400 series (sampling) - levels 1, 2, 3
- ISO 11074 (soil vocabulary)
- ISO 18400-105 (packaging, transport, storage, preservation)
- ISO 28258 (digital exchange of soil-related data)
- Management and accreditation references: ISO 9001, ISO/IEC 17025, ISO/IEC 17020, ISO/IEC 17011, ISO/IEC 17021, ISO/IEC 17065
Keywords: ISO 18400-106, soil quality, sampling, QA/QC, quality assurance, quality control, chain of custody, sampling plan, environmental sampling.
