Radioactive Waste Log

This glossary term is part of the SG Systems Global regulatory & operations guide library.

Updated January 2026 • 21 CFR Part 212 PET drug cGMP, radioactive waste controls, decay-in-storage governance, container identity, activity basis, chain-of-custody, disposal evidence, audit readiness • Primarily PET & radiopharmaceutical operations (cyclotron sites, radiochemistry labs, nuclear pharmacies, hospital PET production)

Radioactive Waste Log is the controlled record set that proves you identified, contained, tracked, stored, moved, and disposed of radioactive waste in a way that protects people, product, and compliance posture. In a PET drug environment governed by 21 CFR Part 212, the log is not “optional admin.” It is evidence that waste did not leak into product areas, that activity was understood and managed over time, that containers were not mixed or mischaracterized, and that final disposition followed defined rules rather than informal habits.

The business value is blunt: radioactive waste is a safety and continuity risk, not a paperwork topic. If waste identity is unclear, you lose time, storage capacity, and confidence, and you increase the odds of a mis-shipment, an exposure event, or a preventable shutdown. The compliance value is equally blunt: auditors don’t accept “we put it in the decay room.” They look for documented control of labeling, segregation, storage, access, movement, release criteria, and disposal proof.

Tell it like it is: most waste programs fail in the gaps between teams. An operator drops a bag in a bin with no container ID. The decay room has “temporary” labels. Someone moves a container to make space and nobody records the move. Later, activity is “estimated” from memory and the basis is never documented. That is how minor sloppiness becomes a major finding. A good radioactive waste log turns weak points into hard, repeatable steps: every container has a unique ID, every move is logged, every release has evidence, and exceptions are handled as controlled investigations instead of quiet cleanup.

“Waste is part of the batch story. If you can’t prove what left the process and where it went, you don’t fully control the process.”

1) What a radioactive waste log is (and what it is not)

A radioactive waste log is a controlled, time-ordered record of waste lifecycle events. It should answer four questions without improvisation:

• What is it? (stream type, isotope, container identity, and activity basis)
• Where is it? (generation point, current location, and every move between locations)
• Who touched it? (handlers, reviewers, and approvals where required)
• How did it leave? (decay release or transfer, with evidence and disposition proof)

It is not a clipboard list that lives in the decay room. It is not a monthly summary made from memory. And it is not “just a radiation safety document.” In a PET operation, waste handling is intertwined with production control: hot cell work creates contaminated consumables, QC generates radioactive liquids, cleaning generates wipes and filters, dose dispensing creates residuals and returns, and any one of those can create contamination pathways if you don’t track what went where.

2) Scope: waste streams, areas, and responsible roles

Start the log design with scope clarity. Define which waste categories are logged, which areas generate waste, and who owns each step. At minimum, scope should cover:

• Generation areas: cyclotron interfaces, radiochemistry hot cells, QC lab, dose dispensing, packaging, and decontamination areas.
• Storage areas: shielded waste staging, decay-in-storage rooms, secured cages, and any interim holding locations.
• Roles: operators generating waste, radiation safety oversight (RSO or designee), QA review where procedures require, and waste disposal coordinators.

Tell it like it is: scope gaps create “orphan waste.” If you forget a room, you will eventually find a bin with no origin data. If you forget a role, you will have containers moved by “helpful” staff who were never trained to log movement. The log should be designed so normal work naturally produces the record.

3) Waste classification: how you define “streams”

Waste classification is the simplest control that prevents the most expensive mistakes. Define streams using categories that match your operation and your disposal routes. A practical stream structure includes:

• Solids: wipes, gloves, PPE, absorbent pads, bench paper, and other non-sharp disposables.
• Sharps: needles, broken vials, glass, and puncture hazards that require specific containers.
• Liquids: aqueous waste, solvent waste, rinse/flush waste, and segregated chemical mixes.
• Filters and columns: sterile filters, cartridges, traps, resin columns, and process components.
• Returns and residuals: unused doses, dose residuals, or returns that re-enter your custody.

The log should record stream type because stream type drives container type, storage location, decay rules, and disposal route. When stream type is missing, people guess later—and later is when errors happen. A controlled stream list also makes training easy: “If it’s sharps, it goes here, it gets this label, and it must have a container ID before the lid closes.”

4) Container identity: labels, IDs, and physical controls

Container identity is the backbone of the waste log. Every waste container must be uniquely identifiable, legible, and durable enough to survive the real environment (cleaning agents, humidity, gloves, shielding, and movement). Practical controls include:

• Unique container ID: barcode/QR plus human-readable ID.
• Stream label: solid/sharps/liquid/filter/return classification.
• Isotope field: primary isotope expected, and a defined “unknown/mixed” option that triggers exceptions.
• Generation location: room/hot cell/QC bench identifier.
• Start time: when the container started collecting waste.
• Status: open/in-use vs closed/sealed vs held vs released.

Physical reality matters. If labels fall off, you will eventually store an unlabeled container, and then your program shifts into guesswork. Use label materials suitable for your environment. Also build a rule that containers without a legible ID are treated as exceptions and are not eligible for normal release pathways.

5) Isotope and activity recording: making estimates defensible

Radiopharmaceutical waste is time-dependent. The log must capture enough information to make decay and release decisions defensible. You do not need perfect precision on every item, but you do need a consistent method and a recorded basis. Common approaches include:

• Known batch linkage: tie waste to a synthesis run where isotope and time anchors are known.
• Known dose linkage: tie returns to dose IDs with activity at calibration time.
• Activity basis: record the method: calculation, instrument reading, or SOP-defined default assumption.
• Time stamps: record the reference time used (EOS, calibration time, or survey time).
• Half-life reference: keep the operational basis consistent and controlled in procedures.

Tell it like it is: “estimated activity” becomes a risk when it’s undocumented, inconsistent, or adjusted after the fact. The solution is not to make operators do physics homework. The solution is to standardize methods: define acceptable estimation approaches per stream, embed calculations where possible, and require users to record the basis used rather than invent one. When you justify a disposal decision, you point to a consistent rule, not a one-off judgment call.

6) Generation capture: where waste is created in the workflow

Waste is generated at predictable moments. If the log is designed around those moments, capture becomes natural. Typical generation points include:

• Hot cell consumables: tubing sets, vials, filters, traps, and wipes used during synthesis and transfer.
• QC testing: sample vials, tips, HPLC fractions, and solvent residues.
• Dispensing and packaging: syringes, shields, dose residuals, and packaging contamination.
• Decontamination: wipes, swabs, absorbents, and cleaning solutions collected during clean-down.
• Maintenance events: filter changes, line changes, and any intervention on contaminated surfaces.

Operational rule: at the moment waste is placed into a container, the container ID must exist and the container must be “in use.” If your process allows “throw it in and label later,” you are selecting for missing data. In a well-designed workflow, the label is printed when the container is created, and critical deposits (especially sharps and liquids) are scan-confirmed.

7) Movement logging: every handoff, every relocation

Movement is where traceability breaks. The log must capture:

• Move events: who moved it, from where, to where, and when.
• Reason codes: routine staging, transfer to decay storage, consolidation, space management, or exception quarantine.
• Access control: only trained/authorized users can execute moves.
• Location model: a real map (room → cage → rack/shelf/bin), not free-text.

Tell it like it is: if movement is not logged, “where is it?” becomes a scavenger hunt. Scavenger hunts aren’t just inefficient; they raise exposure risk and drive mistakes like opening the wrong container. Movement logging should be as routine as inventory movement in a warehouse: no movement without an ID, no ID without a durable label, and no “helpful move” without a record.

8) Segregation and incompatibility: preventing mixing mistakes

Segregation has two goals: radiation safety and chemical safety. Your log should support both by capturing stream metadata and enforcing storage rules. Practical segregation controls include:

• Stream separation: sharps never stored with soft solids; liquids never placed in dry bins.
• Isotope separation: avoid mixing long-lived and short-lived waste if your release strategy depends on timing.
• Chemical incompatibility: segregate solvent waste from aqueous waste where procedures require it.
• Contamination control: designated shielded areas only; no ad hoc storage in hallways or general rooms.

The log becomes powerful when it can enforce “allowed locations” by stream type. If a user attempts to move a liquid container to a solids rack, block it. That is how segregation becomes a system property instead of a training slogan.

9) Decay-in-storage: timing, release criteria, and evidence

Decay-in-storage can be efficient for short-lived isotopes, but only if it is controlled. Your log should define a repeatable decay workflow:

• Entry to decay storage: time the container enters the decay room and the storage position.
• Decay clock basis: the reference time used (container close time, last addition time, or SOP-defined rule).
• Minimum hold period: the “do not release before” rule (often expressed in half-lives).
• Release criteria: what proves eligibility (survey results, calculated threshold, or both).
• Release decision: who authorizes release and whether a second check is required.

Tell it like it is: the biggest failure mode is calendar-based release—“it’s been long enough.” A controlled program replaces guessing with evidence: you measure, or you calculate and verify, but you don’t assume. The log should store the evidence, not just the conclusion.

10) Surveys and checks: how you prove containers are safe to release

Even when decay is predictable, release needs confirmation. The log should record surveys and checks that demonstrate containers meet your criteria. Typical records include:

• Survey time: when the check was performed.
• Instrument ID: which meter was used and its calibration/verification status.
• Measurement type: contact, distance, smear test, or SOP-defined method.
• Result: numeric reading and pass/fail against defined thresholds.
• Reviewer: second-person review when required.

A pass/fail checkbox without a threshold and instrument is weak. The goal is defensible proof that you did not release radioactive material as ordinary waste before it met your criteria. If your workflow supports attaching a photo of a meter display or capturing readings directly, that reduces disputes and accelerates review.

11) Disposal and transfer: manifests, receipts, and closed-loop proof

Disposition is the moment your log must close the loop. Whether you release after decay or transfer to an approved handler, you must capture evidence. Practical disposition records include:

• Disposition type: decay-released to normal waste, transferred to licensed disposal, returned to vendor, or other controlled routes.
• Status transitions: closed → surveyed → released → removed from site control.
• Pickup details: handler identity, date/time, manifest IDs, and container list.
• Receipts: proof of acceptance and final handling where available.
• Exception flags: any disposal via exception path must be reviewed and documented.

Tell it like it is: if you can’t produce receipts, you’re relying on trust. Trust is not an audit strategy. Even for decay-in-storage release, your SOP should define what “released” means and how you prove it.

12) Exception handling: unknown containers and label failures

Exceptions are inevitable. The log must define a controlled ticket concept for conditions such as:

• Unknown container: found with no ID or unreadable label.
• Mixed/unknown isotope risk: isotope not known or inconsistent with expected workflow.
• Damaged container: leaks, compromised lids, or compromised shielding.
• Unauthorized movement: container moved without logging or by unauthorized personnel.
• Disposal mismatch: disposition performed without required evidence.

Controlled response means you isolate, identify, and document—not “fix it quietly.” A good program treats unknown containers like quarantined material: isolate them, restrict access, document investigation steps, and link corrective actions. The log should preserve uncomfortable truth when something went wrong, because that truth is what prevents recurrence.

13) Data integrity: audit trails, edits, and “no reconstruction” posture

The waste log must be credible. That means the same integrity expectations you apply to production records also apply here:

• unique user identities (no shared logins),
• audit trail for edits with reason-for-change,
• event-time capture vs entry-time capture (and how late entries are flagged),
• controlled permissions for release decisions and record closure,
• no routine backdating as “cleanup.”

Tell it like it is: backfilled records are easy to spot. A system that makes logging part of the workflow reduces the urge to reconstruct. If edits are necessary, make them transparent and reviewable.

14) Retention and indexing: finding records under pressure

Retention rules can vary by site and license, but the operational objective is consistent: records must be retrievable. Index the waste log so you can answer real questions fast:

• Container-centric: search by container ID to see full lifecycle.
• Isotope-centric: filter by isotope to evaluate decay strategy and storage pressure.
• Location-centric: show what is currently in each location and why.
• Time-centric: find containers generated or released in a suspect window.
• Disposition-centric: list all releases/transfers with evidence attached.

A common inspection pressure scenario is simple: “Show me what was in the decay room last Tuesday at 3 p.m.” If you can’t answer that, you don’t have a system—you have fragments.

15) KPIs: proving the waste program is controlled

Metrics prevent drift. The waste log should support a small set of KPIs that indicate whether control is improving or degrading:

Rising unknown-container rate is a leading indicator of workflow friction or training gaps. Rising dwell time is often a capacity warning that precedes shortcuts. Metrics don’t solve problems, but they prevent denial.

16) Copy/paste readiness scorecard

Use this scorecard to evaluate whether your waste log is actually executable during peak production.

17) Failure patterns: what breaks waste logs in real life

• Label later culture. Containers enter service without IDs. Fix: create container IDs before first use and require scan confirmation.
• Free-text locations. “Decay room” is not a location model. Fix: rack/shelf/bin locations with scanning.
• Calendar-based release. People guess decay time. Fix: evidence-based release with recorded basis and surveys.
• Mixed streams. Liquids and solids end up together. Fix: stream-based segregation and blocked moves.
• Unowned exceptions. Unknown containers linger. Fix: assign owners, due dates, and escalation rules.
• Disposition proof missing. No manifests/receipts or closure evidence. Fix: attach documents at disposition and require review.
• Reconstruction behavior. Logs completed after the fact. Fix: workflow-native capture and audit trails.

All seven failures are predictable because they happen when logging is treated as “extra work.” The solution is to make logging the fastest way to do the job, not an additional chore after the job.

18) Linkage to production: why waste belongs in traceability

In radiopharma, waste is not separate from manufacturing; it is a byproduct of controlled steps. Linking waste to production improves both safety and investigation speed. Practical linkage patterns:

• Batch linkage: link waste containers to a synthesis batch or hot cell run ID.
• Equipment linkage: link waste to hot cell IDs and cleaning events (useful for contamination investigations).
• QC linkage: link lab waste to test runs when disposal rules depend on solvent type or sample matrices.
• Return linkage: link returned doses to dose IDs and decay-corrected activity basis so storage and release timing are defensible.

Tell it like it is: when something goes wrong—unexpected contamination, a missing vial, or an unexplained survey reading—waste records can be the difference between a one-hour investigation and a one-week shutdown. Waste traceability is operational resilience.

19) Licensing and oversight interfaces: keeping roles clean

Many facilities operate with overlapping oversight: production, QA, and radiation safety. The waste log should make responsibility boundaries explicit so decisions don’t become ambiguous. Practical principles:

• RSO oversight: defines radiation-safety requirements, survey criteria, release thresholds, and escalation rules.
• QA oversight: ensures procedures are followed, records are complete, and deviations are investigated when waste control failures affect controlled areas or product safety posture.
• Operations ownership: executes the workflow, logs moves, and maintains container discipline at the moment work occurs.
• One truth model: the waste log is the system of record for container identity and location history, not a collection of side notes.

This isn’t bureaucracy. It prevents the worst failure mode: “everyone thought someone else approved it.” In controlled environments, approval authority must be explicit, logged, and auditable.

20) How this maps to V5 by SG Systems Global

V5 supports radioactive waste logging by making container identity, movement, and evidence capture workflow-native:

• container creation with unique IDs and label printing (barcode/QR + human-readable),
• scan-driven movement logging with controlled location models (room → rack → bin),
• stream-based segregation rules that can hard-gate invalid moves,
• decay storage workflows with timers, status transitions, and evidence attachment,
• exception tickets for unknown containers, damaged labels, or unauthorized moves,
• audit trails for edits and release decisions aligned to GxP audit trail expectations,
• reporting views that show “what is currently in storage” and “what was disposed” by time window and stream.

When combined with radiopharma production records (hot cell runs, QC tests, dose IDs), V5 can link waste containers to originating activities so investigations move from “what happened?” to “show me the chain” without delay.

21) Extended FAQ

Q1. Why is a waste log relevant to 21 CFR Part 212?
Because PET drug cGMP is about controlled operations and credible records. Waste handling is part of controlled operations: it affects contamination control, safety, and the integrity of your process environment.

Q2. What is the single most important rule for waste log success?
Containers must have IDs before use, and moves must be logged at the time they occur. If either is optional, your log will drift into reconstruction.

Q3. Do we need exact activity values for every container?
Not always. But you need a consistent method and a recorded basis that supports your decay and release criteria and can be defended during inspections.

Q4. What should we do when an unlabeled container is found?
Treat it as a controlled exception: isolate it, restrict access, document investigation steps, record decisions and evidence, and close with corrective actions that prevent recurrence. Don’t normalize unknown containers.

Q5. How do we keep the decay room from becoming a bottleneck?
Use capacity KPIs and evidence-based release workflows. If dwell time is rising, adjust container strategy, segregation, or disposal cadence before space pressure drives shortcuts.

Related Reading (keep it practical)
In radiopharma, time controls everything. End-of-Synthesis Time anchors process timing, Beyond-Use Time defines the patient-use window, and Decay-Corrected Activity keeps activity decisions consistent across handoffs. For credibility, treat waste like a traceable lifecycle with Chain of Custody and Data Integrity expectations, not an afterthought.