Glossary

Chain of custody

A documented, unbroken record of who handled a specimen, from collection through analysis and reporting.

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A defensible drug-test result requires an unbroken chain of custody — every person who touched the specimen is recorded with date and time. Under 49 CFR Part 40, the Federal Drug Testing Custody and Control Form (CCF) is the chain-of-custody document for all DOT-regulated specimens.

Sources & references

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  1. 49 CFR Part 40 — Procedures for Transportation Workplace Drug and Alcohol Testing Programs — U.S. Department of Transportation

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Glossary

Medical Review Officer (MRO)

A licensed physician trained to interpret drug-test results and serve as the medical buffer between the laboratory and the employer.