What is temperature mapping?
Temperature mapping is a documented study that shows how temperature is distributed across a storage area. You place calibrated data loggers throughout a warehouse, cold room or other store and record temperatures under representative conditions. The results prove whether every place where medicines might sit stays within the required range, and they show the warmest and coldest spots, where you then monitor permanently. The EU GDP guidelines require an initial mapping before a storage area is used.
Source: WHO Technical Report Series No. 961, Annex 9, Supplement 8: Temperature mapping of storage areas
T. LozerCompliance Strategy Specialist · entroit GmbH
· Updated
What the GDP guidelines require
Chapter 3 of the EU guidelines on Good Distribution Practice (GDP) sets out four rules for temperature mapping:
| Rule | In practice |
|---|---|
| Map before use | Every storage area is mapped under representative conditions before medicines go in. |
| Place monitors by the results | Permanent temperature sensors sit where the mapping found the largest fluctuations. |
| Repeat when needed | Map again after significant changes to the building or the cooling and heating equipment, and as often as your risk assessment says. |
| Small rooms | For a room of a few square metres at room temperature, assess risks such as heaters and place monitors accordingly. |
The guidelines do not fix the number of loggers or the duration. The WHO technical supplement on temperature mapping describes how to plan, run and report a study in a structured way and is widely used as a reference.
How a mapping study works
- Plan: assess the risks of the area, such as outside walls, the roof, heaters, air vents, doors and loading bays, and justify where the loggers go.
- Measure: record temperatures with calibrated loggers over a period that covers normal operations, including busy and quiet times. Because a warehouse behaves differently in summer and winter, studies usually cover both.
- Report: show whether every position stayed within range, name the hot and cold spots, and define where permanent monitoring sensors go.
Keep the report with your quality records: it is the evidence that your storage zones meet their specification, and inspectors ask for it.
What temperature mapping means for your warehouse system
Mapping proves that a zone is suitable. It does not make sure that the next refrigerated batch actually ends up in the cold room. That happens at every put-away, and that is where the warehouse system takes over: each storage location should carry the temperature range it was qualified for, and the system should block a booking that would put a product in the wrong zone. Inventory management for pharmaceutical wholesale should also record which batch was stored in which zone and when, so you can match it against your temperature data after a deviation. entroit handles cold chain and temperature data alongside batches; the mapping study and the monitoring sensors themselves stay separate tasks.