Posted on December 4, 2025

Reading time: approximately 5 minutes

Drug and alcohol testing is a vital part of maintaining workplace safety, regulatory compliance, and ensuring the integrity of employees. When it comes to testing, one critical aspect that plays a key role in safeguarding both employers and employees is Chain-of-Custody. In this blog post, we will explore what chain-of-custody is, how it works in the context of drug and alcohol testing, and why it matters for both businesses and individuals.

What is Chain-of-Custody?

Chain-of-custody refers to the process of tracking and documenting the handling, transfer, and storage of a specimen from the moment it is collected until the test results are finalized. This protocol ensures that the specimen has not been tampered with, substituted, or contaminated throughout the testing process. In the context of drug and alcohol testing, the chain-of-custody process is especially important for legal and compliance purposes, as it helps verify that the testing process is reliable and accurate.

Why Chain-of-Custody is Crucial in Drug and Alcohol Testing

The integrity of the testing process depends heavily on maintaining a secure and documented chain-of-custody. Without this safeguard, the results of drug and alcohol tests could be called into question, leading to potential legal ramifications or compromised employee safety. A properly managed chain-of-custody guarantees that all parties involved in the testing process adhere to strict protocols, reducing the risk of errors and ensuring that the test results are accurate and trustworthy.

For employers, ensuring that chain-of-custody procedures are followed can also help protect them from legal challenges, disputes, and claims of negligence. It guarantees that drug and alcohol testing was done in compliance with regulatory guidelines, such as the DOT (Department of Transportation) regulations for companies in transportation industries, or other industry-specific standards.

How Does Chain-of-Custody Work in Drug and Alcohol Testing?

Understanding how chain-of-custody works in drug and alcohol testing is essential for both employers and employees. Here’s an overview of the typical process:

Collection of the Sample

The chain-of-custody process begins as soon as the specimen is collected. Whether it's a urine sample, breathalyzer test, or saliva test, the individual collecting the specimen is responsible for documenting every step. This includes verifying the identity of the person being tested and confirming the integrity of the sample. The collector also completes a chain-of-custody form, which outlines details about the sample, such as the time of collection and the names of the individuals involved in the process.

Sealing the Sample

Once the specimen is collected, it is sealed in a tamper-proof container. This ensures that the sample cannot be altered or substituted once it has been secured. A unique identification number, typically a barcode or serial number, is assigned to the sample. This number links the sample to the individual being tested and helps track the specimen throughout the testing process.

Transportation of the Sample

After sealing, the specimen is transported to a certified laboratory or testing facility. During transportation, the chain-of-custody form accompanies the sample. Any transfer of the specimen between individuals must be documented in this form. This documentation creates a comprehensive record of everyone who has had control over the specimen.

Testing and Results Analysis

Upon arrival at the lab, the sample is tested for drug or alcohol content. At this stage, the laboratory personnel follow strict protocols to ensure that no one can tamper with the specimen or compromise the results. The testing process includes verifying the identity of the sample and ensuring that it matches the details on the chain-of-custody form.

Final Results Reporting

Once the specimen has been tested, the results are securely sent to the employer, along with the completed chain-of-custody form. The results are typically kept confidential, and only authorized individuals within the organization should have access to them. The entire process, from sample collection to result delivery, is documented to ensure the reliability and integrity of the test.

The Legal Importance of Chain-of-Custody

One of the key reasons that chain-of-custody is critical in drug and alcohol testing is its legal importance. If an employer faces a situation where the results of a test are challenged—such as in a workplace injury or a dispute over termination—the integrity of the chain-of-custody documentation can be crucial in defending the validity of the test.

If the chain-of-custody process is not properly followed or documented, it opens up the possibility of tampering claims, which could lead to the invalidation of the test results. In some cases, the lack of a solid chain-of-custody record may lead to legal action against the employer, including lawsuits or regulatory penalties. This is especially true in industries that are governed by strict regulations, such as transportation and healthcare, where drug testing is required by law.

Chain-of-Custody in DOT Drug Testing

For employers in industries that require DOT drug testing, such as transportation or public safety, chain-of-custody is even more critical. DOT regulations outline strict procedures for drug and alcohol testing, and any deviation from these standards can result in significant fines, penalties, or even the loss of operating licenses.

The DOT mandates that all drug testing be conducted with a clear, documented chain-of-custody process. This includes:

• Ensuring that specimen collection occurs in a secure and private environment.
• Completing accurate documentation at every stage of the process.
• Using tamper-evident containers to preserve the integrity of the specimen.
• Transporting specimens securely and directly to an accredited laboratory.

In DOT drug testing, any lapse in the chain-of-custody process can lead to serious consequences, including the invalidation of test results and possible legal repercussions for the employer.

How Employers Can Ensure a Secure Chain-of-Custody

As an employer, ensuring a secure and reliable chain-of-custody process is essential for maintaining regulatory compliance and protecting the integrity of drug and alcohol testing in your workplace. Here are some steps employers can take to ensure proper chain-of-custody management:

Work With Certified Collectors

Choose certified collectors who are trained in proper chain-of-custody procedures. Reliable specimen collection is critical to maintaining the integrity of the process.

Use Secure, Tamper-Proof Containers

Ensure that all specimens are placed in tamper-proof containers that seal securely. This helps maintain the integrity of the sample throughout the testing process.

Document Every Step

Accurate documentation is key. Ensure that all information, from collection to testing, is documented clearly and that all relevant parties sign off on the chain-of-custody form at each step of the process.

Partner With Accredited Laboratories

Work with accredited laboratories that are familiar with chain-of-custody procedures and are equipped to handle samples securely.

Implement Training and Procedures

Ensure that all employees involved in the testing process are trained on chain-of-custody procedures and understand the importance of maintaining the integrity of the testing process.

Why Employers Should Prioritize Chain-of-Custody in Drug Testing

Maintaining a secure chain-of-custody is not just a regulatory requirement—it also helps employers create a safe, compliant, and transparent workplace. Prioritizing chain-of-custody in drug testing ensures that:

• The testing process is credible and reliable.
• Test results are defensible in legal or regulatory matters.
• Employees’ privacy and rights are respected throughout the process.
• Workplace safety and compliance standards are maintained.

By understanding and adhering to proper chain-of-custody protocols, employers can avoid legal complications, prevent workplace accidents, and foster a healthier work environment.

Chain-of-custody is an integral part of the drug and alcohol testing process that ensures the integrity, accuracy, and compliance of every test. By following the chain-of-custody procedures, employers can protect themselves from legal issues, maintain a safe workplace, and comply with regulations. Whether you need mobile testing services, on-site specimen collection, or assistance with DOT compliance, we are here to help.

If you're looking for a reliable, professional service to handle your workplace drug testing needs, don’t hesitate to reach out. Get in touch with us today at (574) 344-4443 or email us. We’re ready to support your compliance and workplace safety efforts with expert testing solutions.