Specimen Labeling, Accessioning, and Chain of Custody — Phlebotomy Technician

Objective. Students will apply required labeling elements to a specimen and document it through a simulated accessioning workflow, maintaining an unbroken chain of custody.

Why Labeling and Accessioning Matter

A blood specimen is only as useful as the information attached to it. If a label is missing, illegible, or placed on the wrong tube, the laboratory cannot confidently match results to the correct patient. Errors at this step can lead to misdiagnosis, repeated venipunctures, delayed treatment, or—in the worst cases—patient harm. Specimen labeling, accessioning, and chain of custody are therefore not clerical tasks; they are patient safety functions that fall squarely within your scope of practice as a phlebotomy technician.

Required Label Elements

Most accrediting bodies and regulatory guidelines agree on a core set of elements that every patient specimen label must include:

Patient's full name (first and last, as registered; some facilities also require a middle initial)
Date of birth – used to distinguish patients who share a name
Collection date and time – critical for timed specimens (e.g., glucose tolerance, therapeutic drug monitoring) and for assessing specimen viability
Collector ID – your employee number, initials, or badge ID; this makes you accountable and allows follow-up if a question arises
Accession number – a unique identifier assigned by the laboratory information system (LIS) or manually on a paper log; it links the physical tube to the test order

Some facilities add a patient account or medical record number, the ordering provider's name, and the specimen type or tube color. Always follow your facility's labeling policy, because that policy reflects your employer's compliance requirements.

Label at the bedside or draw site. Never pre-label tubes before you enter the room, and never label a tube away from the patient after collection. Label each tube immediately after it is filled, before you leave the patient's side. Confirm the patient's identity by asking them to state their full name and date of birth, then compare those answers to the requisition and the label—every time, for every patient.

Hand-Printing Labels

When a printer is unavailable or a label must be corrected by hand, print clearly in ballpoint pen. Use block letters. Do not use pencil (it smears and can be altered), do not use felt-tip markers on tubes with colored stoppers (ink can bleed), and never use correction fluid (white-out) to change information on a label. If you make an error, write "error" on the incorrect label, initial it, set the tube aside, and apply a new label.

Accessioning

Accessioning is the process of formally accepting a specimen into the laboratory and assigning it an accession number. In facilities with an LIS, the system generates a barcode label containing the accession number automatically. In facilities using paper logs, the accession number is recorded manually in a bound logbook or on a paper accession log.

A paper accession log entry typically includes:

1. Accession number (assigned sequentially)

2. Patient name and date of birth

3. Date and time of receipt in the lab

4. Tests ordered

5. Specimen type and number of tubes

6. Initials of the laboratory staff member who accepted the specimen

Once accessioned, the specimen is tracked by its accession number through every stage of processing, analysis, and storage. This number is what connects the patient's result report back to the physical tube.

Chain of Custody

Chain of custody (COC) is a documented record of every person who handles a specimen from collection through final disposal. It is mandatory for medicolegal specimens—such as workplace drug screens, forensic samples, and specimens collected for legal proceedings—but the principles apply to all specimens.

A complete COC form records:

Who collected the specimen, and when and where
Who received it from the collector (with date, time, and signature)
Every subsequent transfer, including transport to an outside reference laboratory
How the specimen was stored at each stage

A broken chain of custody means the specimen may be legally inadmissible and scientifically suspect. If even one transfer is undocumented, the integrity of the entire specimen is called into question. In a workplace drug-testing scenario, a broken chain can invalidate the result and expose the employer—and you—to liability.

Practical habits that protect the chain:

Never leave a specimen unattended in an unsecured area.
Seal medicolegal specimens with tamper-evident tape immediately after labeling.
Obtain a signature every time the specimen changes hands—no exceptions.
If you discover a gap in documentation, report it to your supervisor immediately; do not attempt to reconstruct signatures.

Legibility and Correction Policies

Labels must be legible to anyone who handles the tube, not just the person who wrote them. If an accession log entry is illegible, cross it out with a single line, initial and date the correction, and rewrite it clearly. Never obliterate the original entry. These rules exist so that any reader can follow the complete, unaltered history of a specimen.

Summary

Accurate labeling starts with positive patient identification and ends with a tube that carries all required elements in a legible, permanent format. Accessioning links that tube to the test order and to the laboratory's tracking system. Chain of custody documentation ensures that every person who touches the specimen is on record. Together, these three practices protect the patient, protect the laboratory, and protect you.

Key terms8

Accession numberA unique identifier assigned to a specimen upon receipt in the laboratory, used to track it through all stages of testing and reporting.

AccessioningThe formal process of receiving a specimen into the laboratory, assigning an accession number, and recording it in a log or laboratory information system.

Chain of custody (COC)A chronological, documented record of every individual who collects, handles, transfers, or stores a specimen, ensuring accountability and specimen integrity.

Collector IDThe phlebotomist's employee number, initials, or badge identifier recorded on the specimen label to establish accountability for the collection.

Laboratory information system (LIS)Software used by laboratories to manage test orders, generate specimen labels and accession numbers, record results, and track specimens electronically.

Positive patient identificationThe two-identifier verification process (typically full name and date of birth) performed before every draw and before applying a label, to ensure the specimen belongs to the correct patient.

Requisition formA paper or electronic document from the ordering provider that specifies the patient's demographics, the tests ordered, and any special collection instructions.

Tamper-evident sealA sticker or tape applied over a specimen container closure that visibly shows if the container has been opened, required for medicolegal and drug-screen specimens.

In class: Review a facility labeling policy and identify all required label elements (patient name, date of birth, collection date and time, collector ID, accession number) using a sample policy document. · Using mock patient requisition forms, students hand-print labels, apply them to empty training tubes, and log each specimen on a paper accession log, correcting each other's entries against a checklist. · Role-play a chain-of-custody scenario in which a specimen is transferred between three 'personnel' (student pairs); each transfer is documented on a chain-of-custody form and the class discusses what happens when a link is missing.
Materials: Sample facility labeling policy, blank adhesive labels, ballpoint pens, mock patient requisition forms, paper accession log, chain-of-custody form template, empty training tubes
Check: Labeled tube and completed accession log entry reviewed by instructor; all required elements present and legible earns a pass; any missing required element requires immediate correction and re-check.

Practice check8

Answer each question, then check it. Nothing is recorded; this is your own practice.