14 April 2022

WHO publishes practical guide on how to temperature map cold chain equipment and storage areas

On 11th of April 2022, World Health Organization (WHO) published a practical guide How to temperature map cold chain equipment and storage areas developed by the Expanded Programme on Immunization (EPI) of the World Health Organization (WHO) Department of Immunization, Vaccines and Biologicals.

Temperature mapping is the process of recording and mapping temperatures within three-dimensional (3D) spaces, such as cold and freezer rooms, dry storage areas, and refrigerator and freezer units. Temperature mapping and temperature monitoring are integral to the appropriate storage conditions for pharmaceuticals and required by Good Distribution Practice (GDP) Guidelines (Chapter 3.2.1).

Why mapping? To demonstrate by way of documented evidence that the chosen storage area is suitable for the storage of temperature sensitive medicinal products.

An initial temperature mapping exercise should be carried out on the storage area before use, under representative conditions. The results of this mapping should be used to place monitoring devices at areas that experience the most temperature differences and the hot and cold spots. Any potential area that may be unsuitable to store medicines should be identified. Therefore, mapping should be performed before stock is stored. However, it is also recommended to repeat the mapping when the storage area is operating. Afterwards, the mapping exercise should be repeated according to the results of a risk assessment exercise or whenever significant modifications are made to the facility or the temperature controlling equipment. Countries where there are temperature extremes for winter and summer will require, in the first year of commissioning, a winter and summer mapping study.

What to consider:

  • identify crucial storage areas: highest point of storage, heaters, coolers, lighting, windows, doors, loading bays etc;
  • use calibrated monitoring devices in sufficient numbers;
  • record and assess data;
  • repeat mapping to cover for seasonal variations or if the storage area is (subsequently) reconfigured.

The Responsible Person (RP) should be involved during the whole mapping process and fully aware of the mapping exercise findings, risk assessment recommendations and review process. However, the RP involvement does not stop at the mapping process, since RP needs to be able to demonstrate supervision and review of subsequent daily minimum/maximum routine temperature monitoring and recording and should be consulted in the event of any temperature excursions.