Re-map after significant changes to HVAC, layout, doors, packout or routes, or at a defined interval from your risk assessment.

Temperature Mapping

Q: How many sensors do I need?

Use a grid that resolves vertical and horizontal gradients, plus targeted placements near doors, evaporators and suspected extremes. Justify sensor density to risk and size.

Q: Do I have to map both empty and loaded?

Usually yes. Empty mapping finds structural hot/cold spots; loaded mapping tests airflow and thermal mass effects. For transport, qualify both full and minimal loads.

Q: How long should mapping run?

Long enough for steady state and representative operation plus challenges. Seasonal studies or simulated extremes may also be justified by risk.

Q: Is MKT always appropriate?

No. Use MKT when cumulative thermal stress aligns with stability knowledge; for hard limits, time-out-of-range and absolute limits may be more relevant.

Q: Should I map humidity too?

Map RH when product or packaging is humidity-sensitive; otherwise justify temperature-only mapping in the risk assessment.

Temperature Mapping – Storage/Transport Qualification

This topic is part of the SG Systems Global regulatory & operations glossary.

Updated October 2025 • Cold Chain, Warehouse Rooms, Vehicles & Shippers • QA, Validation, Logistics

Temperature mapping is the structured study that proves a storage area or transport solution (from ambient warehouses to cold rooms, freezers, reefers and insulated shippers) can maintain product label conditions under real‑world stresses. In regulated industries, mapping is a prerequisite to qualifying the environment for use and a guardrail for ongoing GDP/GMP compliance. It characterizes hot and cold spots, validates alarms, and defines operating limits so that routine monitoring, deviations, and release decisions are all grounded in evidence rather than assumption.

“Temperature mapping turns a room, truck, or shipper from a black box into a qualified control step you can trust.”

TL;DR: Map storage and transport environments with calibrated loggers to locate hot/cold spots, challenge under worst‑case loads and seasons, verify alarms, and set evidence‑based limits. Use the results to qualify the space/shipper, drive QRM controls, and integrate alerts and holds in MES/WMS so excursions trigger Deviation/CAPA and block release until assessed.

1) What Temperature Mapping Covers—and What It Does Not

Covers: the documented characterization of temperature behavior across 3‑D space and time for storage rooms, fridges/freezers, cages, mezzanines, vehicles and shipping systems. It demonstrates that specified ranges (e.g., 2–8 °C, 15–25 °C, ≤‑20 °C) are maintained with representative loading, door openings, defrost cycles, power interruptions, and seasonal extremes. It encompasses sensor planning and calibration, study protocols, analysis (including mean kinetic temperature where appropriate), alarm verification, and the definition of routine monitoring positions.

Does not cover: routine environmental microbiology (EM) or product stability claims (see Stability Studies). Mapping validates the environment that houses the product; stability validates the product within that environment.

2) Legal, System, and Data Integrity Anchors

Regulators expect storage and transport to be demonstrably fit‑for‑purpose. That means qualification aligned to GDP/GMP principles, documented under Document Control, and supported by validated systems (Annex 11/Part 11) with audit trails. Sensors and data loggers used for mapping and routine monitoring must be covered by IQ/OQ/PQ, maintained in current calibration status, and traceable to national standards. Changes to HVAC, racking, packout, or lane design trigger MOC and may require re‑mapping.

3) The Evidence Pack for Qualification

A robust mapping dossier reads like a validation package. It contains a user/set‑of‑requirements statement and risk assessment; drawings with logger locations; a protocol detailing sensors, accuracy, sample rate, study duration, loads, and challenges (doors, power, defrost); calibration certificates; raw time‑series and summaries; worst‑case hot/cold spot identification; alarm setpoint/response checks; acceptance criteria and deviations; conclusions, routine monitoring map positions, and requalification triggers. Where mass‑to‑volume claims are relevant, include density/thermal mass rationale for packouts used during transport mapping.

4) From Project Kickoff to Qualified Storage/Transport—A Standard Path

1) Plan & assess risk. Define intended range(s), occupancy patterns, and worst‑case scenarios in the Risk Register.
2) Design the study. Choose sensor type/accuracy, count and placement grid, sampling interval, load configuration, and stress tests; approve under Document Control.
3) Execute mapping. Perform empty and loaded studies (storage) or shipper/vehicle lane trials (transport), including seasonal runs when justified.
4) Analyze & qualify. Identify hot/cold spots, verify alarms, set routine monitoring points, and issue a qualification report with requalification criteria.
5) Operate & maintain. Implement routine monitoring, alarm response SOPs, and periodic review; re‑map on material changes or at defined intervals.

If any prerequisite (e.g., sensor calibration, HVAC setpoint control) fails during execution, halt the study, raise a Deviation, correct, and resume with clear data segregation.

5) Study Design—Sensors, Hot/Cold Spots, Doors & Defrost

Sensor quantity and placement should resolve vertical stratification, wall effects, door turbulence, and airflow shadows. Denser grids are justified for large rooms, high‑bay racking, or high‑risk ranges (e.g., vaccines). Place loggers near suspected extremes—high shelves near roof lights, near evaporators, adjacent to doors, and deep inside pallets. Include at least one reference sensor proximate to the control probe. Challenge door opening patterns that reflect real operations, not idealized behavior, and explicitly capture defrost cycles or compressor staging that can cause oscillation and transient spikes.

6) Measurement Uncertainty, Calibration & Traceability

Choose sensors with accuracy commensurate to the label range and acceptance bands. Pre‑ and post‑study verification against a traceable reference reduces uncertainty and protects data credibility. Record serial numbers, calibration certificates, offsets applied, and minimum/maximum reading capabilities. For transport, pair shipment loggers with a temperature‑conditioned start to avoid warm‑start bias, and verify time synchronization to support excursion reconstruction.

7) Data Integrity—Proving the Proof

Mapping data must be attributable and immutable. Capture logger IDs, locations, and placement photos; retain raw files with checksums; and document any data exclusions with scientific rationale. Perform analysis in validated tools under Annex 11/Part 11 control. Link the mapping record to ongoing monitoring locations so inspectors can trace “why here?” for each permanent probe or logger.

8) Duration, Loading & Seasonal Extremes

Duration should cover steady state plus representative operation. Empty studies help find structural hot/cold spots; loaded studies add thermal mass and airflow obstruction. For transport, qualify both best‑case (full shipper/vehicle) and worst‑case (minimal thermal mass) loads. Where climate drives risk, perform mapping during hot and cold seasons or simulate with environmental chambers. Document the chosen approach and its justification in the risk assessment.

9) Equipment, Facilities & Packout Interactions

HVAC setpoints, defrost schedules, door seals, dock shelters, and racking geometry interact to shape temperature fields; packout recipes (gel packs, phase‑change materials, cartons) govern transport profiles. Treat each as a controllable factor: pre‑cool times, packout conditioning, and placement of refrigerants relative to product matter. If mapping reveals sensitivity (e.g., top‑layer warming at doors), codify mitigations in SOPs and operator training.

10) Alarms, Excursions & Release Decisions

Mapping should prove that alarms are set where they can prevent product impact, not merely record it. Confirm detection, notification paths, and time‑to‑response during challenges. After qualification, treat excursions via predefined decision trees aligned to label stability knowledge and Stability Studies. Disposition flows through Hold/Release and Lot Release, with impact bounded by time‑temperature integration (including MKT where appropriate) and traceability to affected SSCC/locations in the WMS.

11) Warehouse Status, Holds & Distribution Readiness

Only qualified storage and transport should be released for use. Configure the WMS so inventory can only be stored in qualified locations, with Quarantine/Hold enforced for new or changed areas until mapping closes. For shipping, require a qualified route/shipper selection before generating the ASN. Post‑shipment logger data should reconcile to the shipment record to complete the chain of custody and enable Recall Readiness.

12) MKT and Time‑Out‑of‑Range (TOR)

Mean kinetic temperature (MKT) compresses variable profiles into a single thermal stress metric that can align to stability knowledge, while time‑out‑of‑range (TOR) focuses on absolute limits and duration. Use both thoughtfully: MKT for cumulative effect within a known stability envelope, TOR for hard guardrails. Mapping defines which metric is relevant for each storage class or packout and how to calculate and interpret it consistently across batches and lanes.

13) Metrics That Demonstrate Control

Max spatial delta‑T between hottest and coldest point at steady state.
Door‑event recovery time to return all positions to range.
Alarm effectiveness (detection to response time) in challenge tests.
Percent time within range by position and season; MKT vs. spec where applicable.
Transport lane success rate (qualified shipments without excursion).
Requalification on‑time rate for rooms, vehicles, and shippers.

Together these KPIs quantify risk, operational resilience, and validation health of the cold chain.

14) Common Pitfalls & How to Avoid Them

Mapping only empty or only loaded. Do both where risk warrants; they answer different questions.
Too few sensors. Under‑sampling hides hot/cold spots; justify grid density to risk.
Unverified alarms. Challenge setpoints and notification paths during mapping, not after go‑live.
Uncalibrated or drifting loggers. Lock calibration status and verify pre/post study.
Ignoring seasonality. Map during extremes or simulate; document rationale either way.
No link to operations. Mapping means little if routine probes are placed arbitrarily; tie them to mapped extremes.

15) What Belongs in the Qualification Record

Identify the asset or lane (room ID, vehicle, shipper SKU), intended ranges, study design and dates, sensor metadata and calibrations, raw data repository, analyses and results, identified hot/cold spots, alarm verification outcomes, acceptance decisions with deviations/CAPA, defined monitoring points, and requalification triggers. Cross‑reference to change controls and stability rationale where limits derive from product knowledge. Retain per Record Retention policy.

16) How This Fits with V5 by SG Systems Global

Templates & Scheduling. In the V5 platform, temperature‑mapping templates define sensor grids, dwell times, door challenges, and acceptance criteria by storage class or shipper type. A scheduler tracks due requalification and seasonal studies, raising tasks and holds when dates or conditions lapse.

Data Acquisition & Integrity. V5 ingests logger and IoT telemetry with authenticated device IDs, enforces audit trails, and binds data to specific assets/lanes. Calibration status for each sensor resides under Asset Calibration Status; out‑of‑status devices auto‑flag studies and block qualification reports.

Analysis & Decision Support. Built‑in calculators produce MKT and time‑out‑of‑range metrics, identify hot/cold spots, and verify alarm performance. Results flow into the Risk Register and generate routine probe placement maps that operations can view on mobile devices during installation.

Operational Interlocks. The V5 WMS prevents storage in unqualified locations, enforces Quarantine/Hold on impacted stock during excursions, and links shipments to qualified routes/packouts. Generating an ASN requires a lane/shipper combination with current qualification; shipment loggers can be scanned to the load and reconciled on receipt.

Exception Management & Traceability. Excursions open guided Deviation workflows with decision trees that reference stability knowledge and mapped limits; approved dispositions propagate to lots, locations and SSCC pallets. Dashboards trend performance across rooms, vehicles and carriers to target the biggest risk reduction first.

Bottom line: V5 turns mapping from a once‑a‑year exercise into a living control—templates, telemetry, analysis and interlocks ensure storage and transport stay qualified, not just once, but every day.

17) FAQ

Q1. How many sensors do I need?
Enough to resolve meaningful gradients. Use a grid that covers corners, center, heights, and known risks (doors, evaporators). Higher risk or larger spaces justify denser grids; document your rationale.

Q2. Do I have to map both empty and loaded?
Typically yes for storage: empty to find structural extremes; loaded to assess airflow and thermal mass effects. For transport, test best‑case and worst‑case packouts and loads.

Q3. How long should mapping run?
Long enough to reach steady state and capture representative operations, plus challenges. Many run several days to a week; seasonal studies or simulated extremes may also be justified.

Q4. When must I re‑map?
On significant change (HVAC upgrades, layout/racking changes, door modifications, different packout materials/quantities, new routes) or at a defined interval from your risk assessment.

Q5. Is MKT always appropriate?
No. Use MKT when cumulative thermal stress links to stability; for tight hard limits (e.g., frozen), absolute excursions and time‑out‑of‑range may be more relevant. Align with product stability knowledge.

Q6. Should I map humidity too?
Where product or packaging is humidity‑sensitive, yes—include RH mapping and controls alongside temperature; otherwise justify why temperature alone is sufficient.