Chain of Custody
Summary
Chain of custody refers to the documented process used to track the collection, handling, transfer and analysis of samples from the point of sampling through to laboratory testing and reporting. It is a critical quality assurance measure in environmental, contaminated land, asbestos and occupational hygiene investigations.
Maintaining a clear and defensible chain of custody helps ensure that analytical results are reliable, traceable and suitable for regulatory, legal or compliance purposes.
Definition
Chain of custody is a formal record that documents the possession, handling and transfer of samples throughout the sampling and analytical process. It typically records details such as sample identification, collection time and location, preservation methods, transfers between personnel and receipt by the laboratory.
A completed chain of custody provides assurance that samples have not been tampered with, mixed up or compromised prior to analysis.
Why Chain of Custody Matters
From a data quality perspective, chain of custody underpins the integrity of laboratory results. Without a clear record of how samples were handled, the validity of analytical results may be questioned.
Chain of custody is also important for regulatory and legal defensibility. Environmental reports, asbestos assessments and remediation validation documents may be reviewed by regulators, auditors or third parties who rely on chain of custody records to confirm that sampling and analysis were conducted appropriately.
For practical project delivery, chain of custody helps avoid disputes, re-sampling and delays by clearly documenting responsibilities and sample movements from field to laboratory.
When Chain of Custody Is Required
Chain of custody procedures are typically required for:
Any assessment where laboratory results support regulatory or compliance decisions
In many cases, a completed chain of custody form must accompany samples submitted to the laboratory.
Typical Information Included in a Chain of Custody Record
A chain of custody record commonly includes:
Unique sample identification numbers
Sample location, date and time of collection
Sample type and preservation method
Requested laboratory analyses
Details of sample transfer and receipt
Signatures or confirmations of custody changes
The level of detail may vary depending on project requirements and laboratory procedures.
Legislative and Regulatory Context
While chain of custody is not always explicitly mandated in legislation, it is an established requirement under recognised environmental and occupational hygiene practices.
Regulators, auditors and laboratories expect chain of custody records to be maintained as part of quality assurance and quality control frameworks supporting environmental and asbestos-related work.
How We Can Help
Our work includes:
Preparation and management of chain of custody documentation
Coordination of sample handling and laboratory submission
Review of laboratory records for completeness and traceability
Integration of chain of custody records into reporting and validation documentation
We focus on maintaining clear, defensible records that support data integrity and regulatory confidence.
Related Terms and Concepts
Sampling and Analysis Plan
Environmental Site Assessment
Contaminated Land
Asbestos in Soil
Air Monitoring
Waste Classification
Site Validation