Who is responsible for maintaining the chain of custody?

• A. The project manager
• B. The lab inspector
• C. A designated third-party courier
• D. The lead dust sampling technician, until they transfer custody of the samples

Answer: (D)

Maintaining the chain of custody means keeping a verifiable, unbroken record of who had control of each sample from the moment it’s collected until it’s analyzed. The person who collects the samples—the lead dust sampling technician—must hold custody from collection and preserve the sample’s integrity up to the point they hand it to the next custodian. This includes properly sealing and labeling the sample, and documenting all details (time, date, location, sample ID) along with signatures or initials of the people who handled it. This careful handoff ensures the results are defensible and traceable, which is essential for regulatory clearance. A designated courier may take custody during transport, but only after the technician has completed the transfer. The project manager oversees the project, and the lab inspector focuses on the testing process, not on on-site custody; their roles don’t replace the on-site technician’s responsibility to maintain the chain of custody until transfer.