Cold chain
Temperature excursion records for cold chain shipments
A temperature excursion is any time a product spends outside its required temperature range. Whether that matters depends on how far, how long, and what the product can tolerate. None of those questions can be answered without a record that was made at the time and can be tied to the shipment and to whoever had custody.
Check the rules that apply to your product. Food, medicines, vaccines and clinical supplies are each subject to their own regulations, guidance and customer quality agreements. This guide describes general documentation practice and is not a substitute for those requirements.
What counts as an excursion
The required range comes from the product owner: a label storage condition, a specification, or a quality agreement. An excursion is defined against that range, often with a time element. A short spike during a door opening may be acceptable for one product and a rejection for another. Write the definition down before the shipment moves, so nobody argues about it afterward.
- Range: for example 2 to 8 °C, or frozen at or below a stated temperature.
- Tolerance: any allowed time outside the range, and any cumulative limit.
- Measurement point: air in the trailer, return air at the unit, or product temperature.
- Logging interval: how often readings are taken. A long interval can miss a short excursion entirely.
What to record for every temperature-controlled shipment
| Stage | Record |
|---|---|
| Before loading | Required range and setpoint on the shipping instructions; trailer or container pre-cooled; unit setpoint and mode; logger ID and start time |
| Loading | Product temperature at loading, door-open time, loading pattern, seal number |
| In transit | Continuous logger readings; reefer unit data if available; alarms and who responded |
| Each handover | Reading at handover, time the doors were open, who took custody |
| Delivery | Product temperature on arrival, logger stopped and downloaded, readings noted on the proof of delivery |
When an excursion happens
- Protect the product. Restore the correct temperature and move the product to proper storage if the vehicle cannot hold it.
- Quarantine, don't discard. Keep the product separate and clearly marked until the owner decides what happens to it.
- Preserve the data. Stop and download the logger without altering it. Keep the raw file, not just a printout or summary.
- Notify the product owner with the shipment reference, logger data and what is known about the cause.
- Record the event using the template below.
- Wait for disposition. Release, reject or further testing is usually the product owner's decision, based on its stability data.
- Close the loop with a corrective action: what will prevent the same cause next time.
Excursion report template
| Field | Content |
|---|---|
| Shipment | References, product, lot or batch numbers, quantity |
| Required range | Range, tolerance and measurement point |
| Excursion | Start and end time, minimum or maximum temperature reached, duration outside range |
| Location and custody | Where the goods were, and which party held them, during the excursion |
| Data source | Logger or sensor ID, calibration status, logging interval, file name |
| Probable cause | For example unit failure, door left open, delay at a handover, wrong setpoint |
| Immediate action | What was done and when |
| Disposition | Decision, who made it and on what basis |
| Corrective action | What changes, and who owns it |
Common causes, and the record that exposes them
| Cause | What the record shows |
|---|---|
| Wrong setpoint | A steady temperature, but at the wrong value from the start |
| Warm product loaded | High product temperature at loading, slowly falling |
| Long dock dwell | A rise that lines up with a handover or a warehouse receipt |
| Unit failure or fuel outage | A steady climb, often with a unit alarm |
| Power off during transfer | A gap in unit data while the logger keeps recording |
| Poor airflow | Uneven readings between loggers placed in different positions |
The pattern alone rarely proves cause. Matching the time of the excursion to the custody record, which shows who held the goods and when doors were opened, usually does.
Making the data trustworthy
- Use calibrated devices and keep the calibration records.
- Synchronize clocks. A logger that is an hour out makes every comparison with the custody record wrong.
- Keep the original file. Summaries and screenshots are useful but can be disputed.
- Label readings with their source and age, especially on live dashboards, so an old reading is never mistaken for a current one. The same principle is covered in shipment visibility.
- Keep records for as long as your regulations, contracts and claim periods require.
Instructions that prevent disputes
Many temperature claims turn on what the carrier was told. Put the setpoint, the required range, the unit mode (continuous or start-stop) and any pre-cooling requirement on the bill of lading or shipping instructions, in writing, every time.
Excursions and claims
A temperature excursion claim usually turns on three things: the agreed temperature instructions, proof of the product's condition at loading, and evidence of when the excursion happened and who had custody. If the carrier was given clear written instructions and the log shows the excursion during its leg, the claim is much simpler. Note the reading at delivery on the delivery receipt, and follow the freight claim process within the contractual time limit.
Operators who already run reefer telematics can bring those readings into the same record as the handovers. Cargovate for shippers works with the tracking devices and telematics an operator already has.
Common questions
What is a temperature excursion?
Any period when a product is outside its required temperature range. Whether it affects the product depends on the size and length of the excursion and the product's stability.
Who decides if product can be used after an excursion?
Usually the product owner or manufacturer, based on its stability data and quality procedures. Carriers and warehouses should quarantine the product and report, not decide.
Is the reefer unit's display enough evidence?
It helps, but it may measure air rather than product and may not keep a full history. An independent, calibrated logger with the raw data file is stronger.
How often should a logger record?
Often enough to catch the shortest excursion that would matter for the product. The product owner's requirements should set the interval.
Last reviewed 2026-09-17