Cold room temperature:
GDP traceability in practice.

Good Distribution Practice requires the temperature of medicines to be monitored and recorded across the entire chain. What is not always clear is what makes that record valid as auditable evidence.

What GDP establishes

Good Distribution Practice (GDP) frameworks govern how medicines are distributed, stored and transported. They require continuous control and recording of temperature conditions across the chain, from storage to delivery.

Records must be kept and available for inspection. The storage temperature must be maintained within the range specified in the product registration, which varies by medicine.

Thermal mapping of the environment

Before defining the sensor installation point, the cold room or refrigerated environment should undergo thermal mapping: a procedure that identifies the coldest, warmest and most unstable temperature zones within the space.

Monitoring without prior mapping means the sensor may not be positioned at the critical point, and the collected data may not represent the actual condition of the product.

What a traceable record must contain

For a temperature history to have value as audit evidence, it must include, at a minimum:

• Identification of the measuring equipment (serial number or ID)
• Date and time of each reading (timestamp)
• Recorded value
• Identification of deviations and a record of the actions taken

Sensor calibration is part of traceability

A temperature reading only has evidentiary value if the instrument that produced it has calibration traceable to national or international standards. A sensor without a valid calibration certificate does not support the traceability required in a regulatory audit.

Calibration should be performed by an accredited calibration laboratory (ISO/IEC 17025, ILAC-MRA), which provides metrological traceability.

A record exists when data is stored. Traceability exists when that data carries instrument identification, a timestamp and traceable calibration. Without all three elements, the history does not serve as auditable evidence.