A refrigerated vehicle is not a small warehouse on wheels. It moves, its refrigeration unit cycles with the engine or a separate power pack, its doors open repeatedly at every stop, and its load shifts. The static cold room or chamber mapping study, and the shipper chamber qualification, both assume a controlled test environment; neither one characterizes what actually happens inside a delivery van’s cargo box on a real multi-stop route. This protocol closes that gap. Replace every <<FILL: ...>> placeholder, set your document numbers and dates, and route it through your normal validation and document control process. A worked filled specimen follows. Verify each cited standard against the current published version before you rely on it. This is educational reference content, not regulatory or legal advice; adapt it to your fleet and routes.
Approval page
| Field | Entry |
|---|---|
| Document title | Temperature Mapping of Refrigerated Vehicle <<FILL: vehicle ID / fleet type>> |
| Document number | <<FILL: PROT-ID, e.g. VAL-CC-041>> |
| Version | <<FILL: version>> |
| Effective date | <<FILL: effective date>> |
| Supersedes | <<FILL: prior version or "New">> |
| Product / product family carried | <<FILL>> |
| Storage claim under test | <<FILL: e.g. 2 to 8 degrees C>> |
| Route type under test | <<FILL: single-drop line-haul / multi-stop last-mile>> |
| Approval | Name | Signature | Date |
|---|---|---|---|
| Author (Validation) | <<FILL>> | ||
| Reviewer (Cold chain / Logistics SME) | <<FILL>> | ||
| Reviewer (Fleet / Transport operations) | <<FILL>> | ||
| Approver (Quality Assurance) | <<FILL>> |
1. Objective
To demonstrate, with reproducible data, that the cargo box of the defined refrigerated vehicle holds the product within its labeled storage range <<FILL: e.g. 2 to 8 degrees C>> throughout a representative route profile, including engine idle and shutdown periods, defrost cycles, and the door-open events of a realistic delivery pattern.
2. Scope
This protocol maps one vehicle configuration: a fixed refrigeration unit setpoint, cargo box loading configuration, and bulkhead or curtain arrangement, run over a representative route. It does not qualify the shipper packaging inside the vehicle, which is qualified separately (see the shipper packaging qualification protocol), and it does not qualify the lane end to end across handoffs and carriers, which is qualified separately (see the shipping lane qualification protocol). This protocol answers a narrower question: does the vehicle itself hold range for the product sitting directly on the cargo box shelving or in bins, independent of any secondary packaging. Any change to the refrigeration unit, insulation, door seals, load configuration, or route pattern invalidates this qualification and requires requalification under <<FILL: SOP-ID for change control>>.
3. System description
| Element | Specification |
|---|---|
| Vehicle ID / fleet type | <<FILL: e.g. box van, straight truck, last-mile courier van>> |
| Refrigeration unit | <<FILL: make/model, engine-driven or standby-electric, setpoint>> |
| Cargo box construction | <<FILL: insulation type, door seal type, single or multi-compartment>> |
| Load configuration under test | <<FILL: shelving layout, minimum and maximum load>> |
| Power source during stops | <<FILL: engine idle, standby electric, battery-only hold time>> |
| Route pattern under test | <<FILL: number of stops, average stop duration, total route time>> |
4. Prerequisites
- The vehicle refrigeration unit is installed, commissioned, and its own setpoint controller is verified against a reference thermometer.
- Data loggers are calibrated, traceable to a national standard, with pre-use calibration current and post-use verification planned (accuracy
<<FILL: e.g. plus or minus 0.5 degrees C>>). - A route or route simulation is defined and agreed with fleet operations, representative of the worst-case realistic delivery pattern (most stops, longest total time, hottest or coldest season).
- The vehicle door-open procedure and driver load-securing instruction are drafted and available.
- The risk assessment identifying this vehicle class and route as requiring mapping is complete (see the cold chain distribution route risk assessment).
5. Roles
| Role | Responsibility |
|---|---|
| Validation engineer | Executes the protocol, places loggers, records raw data and door-open timing, drafts the report. |
| Cold chain / Logistics SME | Defines the representative route pattern, load configuration, and seasonal timing. |
| Fleet / Transport operations | Provides the vehicle and driver, executes the route or simulation, confirms real-world representativeness of stop counts and durations. |
| Quality Assurance | Approves the protocol and report and dispositions any out-of-range result. |
6. Mapping conditions and sensor plan
Map at minimum a hot season and a cold season condition, since ambient extremes change how the refrigeration unit performs and how quickly a cargo box recovers after a door opens.
| Element | Specification |
|---|---|
| Sensor count and placement | <<FILL: minimum 6 to 9 for a single-compartment van; front near the unit, rear near the doors, floor and shelf level, plus one ambient logger outside the cargo box>> |
| Door-open simulation | Open the rear (and side, if fitted) doors for <<FILL: e.g. 90 seconds>> at each simulated stop, matching the real average dwell time observed on the route |
| Number of simulated stops | <<FILL: e.g. 12, matching the worst-case route stop count>> |
| Engine-off / idle periods | Include at least one extended engine-off period of <<FILL: duration>> to capture standby-electric or battery-hold performance, if applicable |
| Defrost cycle capture | Run long enough to capture at least one full defrost cycle of the refrigeration unit |
| Duration | Full worst-case route time plus margin <<FILL>> |
7. How to execute: step by step
- Confirm the refrigeration unit setpoint and calibrate loggers; record calibration certificates.
- Place loggers per the sensor plan; document positions with a diagram and photographs.
- Load the cargo box to the defined configuration (minimum and maximum load runs are both required, see test cases).
- Start the route or route simulation; record actual departure time, each stop’s start and door-open duration, and arrival time.
- Capture any engine-off period and any observed defrost cycle in the run log.
- Retrieve loggers at route completion; perform post-calibration check and download data.
- Analyze: minimum, maximum, mean, and time-out-of-range per sensor location; identify the worst-case location (commonly near the rear doors).
- Confirm whether the worst-case location recovers to range within a defined time after each door-open event.
- Repeat for the second seasonal condition.
- Write the report; define the routine monitoring probe location and any requalification triggers.
8. Acceptance criteria
A run passes when all of the following are true:
- Every cargo-box logger stays within the product range
<<FILL: e.g. 2.0 to 8.0 degrees C>>for the full route duration, excluding a qualified transient recovery window after a door-open event. - Recovery to range after each door-open event occurs within
<<FILL: e.g. 5 minutes>>. - No freeze event occurs for a freeze-sensitive product, including during any engine-off or extended-stop period.
- The worst-case sensor location is identified and the routine monitoring probe is placed there or conservatively bounds it.
- Results are reproducible across the required seasonal conditions and load configurations.
- Post-use logger drift is within tolerance, or the run data is invalidated.
9. Test cases
| TC ID | Season | Load | Stops simulated | Worst-case location min (C) | Worst-case location max (C) | Time out of range | Freeze event | Pass/Fail | Tester | Date |
|---|---|---|---|---|---|---|---|---|---|---|
| TC-01 | Summer | Max | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL: Y/N>> | <<FILL>> | <<FILL>> | <<FILL>> |
| TC-02 | Summer | Min | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> |
| TC-03 | Winter | Max | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> |
| TC-04 | Winter | Min | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> | <<FILL>> |
Add rows for any additional route pattern (for example, a shortened express route versus a full multi-stop route) that the fleet actually runs.
10. Deviation handling
Any out-of-range run, invalid logger, missed door-open simulation, or departure from the defined route pattern is recorded as a protocol deviation with an assessment of impact on the conclusion. Route deviations per <<FILL: SOP-ID for deviations>> and have QA disposition before the report is finalized.
11. Summary and conclusion
State whether the vehicle configuration met all acceptance criteria across every season and load. Record the qualified claim (product range, maximum stop count and dwell time per stop, maximum total route time, seasons qualified), the conditions that would trigger requalification (refrigeration unit service or replacement, route pattern change, added stops, door seal replacement), and the routine monitoring probe location. QA signs the conclusion.
12. Attachments
- Calibration certificates and post-use verification for every logger.
- Route log: departure, each stop’s start time and door-open duration, arrival.
- Photo-documented sensor placement and load configuration.
- Raw logger data files (retain the raw file, not only an auto-generated report).
- Any deviation records.
Filled specimen
The following shows one completed test-case set for a last-mile delivery van holding 2 to 8 degrees C over a 12-stop route. Values are illustrative; replace them with your own.
| TC ID | Season | Load | Stops simulated | Worst-case location min (C) | Worst-case location max (C) | Time out of range | Freeze event | Pass/Fail |
|---|---|---|---|---|---|---|---|---|
| TC-01 | Summer | Max | 12 | 3.1 | 7.6 | 0 h | N | Pass |
| TC-02 | Summer | Min | 12 | 2.8 | 8.0 (transient at door, recovered in 3 min) | 0 h sustained | N | Pass |
| TC-03 | Winter | Max | 12 | 2.4 | 6.9 | 0 h | N | Pass |
| TC-04 | Winter | Min | 12 | 2.2 | 6.5 | 0 h | N | Pass |
Conclusion in the specimen: the vehicle held 2.0 to 8.0 degrees C throughout a 12-stop route in both seasons at minimum and maximum load, with brief door-open transients recovering within the defined 5-minute window and no freeze event. The routine monitoring probe was placed at the worst-case location, the rear shelf nearest the doors. Any change to route stop count above 12, refrigeration unit service, or door seal replacement triggers requalification.
Common inspection findings this protocol prevents
- Only the shipper packaging is qualified, and the vehicle cargo box itself is assumed to hold range with no data behind that assumption.
- Mapping is run with the vehicle parked and doors closed the whole time, which does not represent an actual multi-stop delivery pattern.
- No engine-off or standby-power period is tested, so a real delivery-day power interruption is unqualified territory.
- Worst-case location is assumed instead of measured, and the routine monitoring probe sits somewhere convenient rather than at the mapped hot or cold spot.
- A single vehicle in a fleet is mapped once and the result is applied to every other vehicle and route without justification.
How to adapt this protocol
- Set your document number, vehicle configuration, storage range, and route pattern on the approval page.
- Enter the real refrigeration unit, cargo box construction, and load configuration in section 3.
- Build the door-open and stop-count simulation in section 6 from actual route data, not an assumed pattern.
- Decide whether every vehicle in a fleet needs its own study or whether a documented, risk-justified bracketing approach across similar vehicle classes applies, and state that rationale in section 2.
- Point the deviation and change-control cross-references to your real procedures.
- Confirm the current version of every referenced standard before issue.