Temperature Mapping and WHO

There are a number of industry regulations from all around the world that explicitly and implicitly require temperature mapping as a documented process to demonstrate adequate temperature conditions are maintained for storage of temperature-sensitive pharmaceutical products.  However, most of those regulations provide little guidance as to the specifics on how an appropriate temperature mapping should be performed. In recent years, USP, ISPE and PDA have all begun to provide some specific mapping guidance and best practices to the industry with recommendations for mapping duration, frequency, locations, etc.

In May 2015 the World Health Organization (WHO) issued Supplement 8, “Temperature mapping of storage areas” to their own WHO Technical Report Series, No. 961, 2011.  Several regulatory authorities,  particularly European agencies such as the HPRA, refer to these WHO guidelines.  Supplement 8 is specific to temperature-controlled storage areas designed for long-term or short-term storage of temperature-sensitive products including freezer rooms, cold rooms, temperature-controlled storage areas, quarantine areas and receiving and loading bays.  The supplement provides the following guidance for a temperature mapping protocol that should be reviewed and approved to ensure the mapping study is correctly carried out:

  • Approval page and change control history
  • Acronyms and glossary
  • Description and rationale – describe the installation to be mapped
  • Scope – define the purpose of the mapping study and if there is a need for seasonal mappings
  • Objectives – plan to measure temperature variations (door openings, day of the week/time of day, heating, cooling, ventilation, airflow variations), identifying acceptable and non-acceptable storage areas, locations for routine monitoring.
  • Methodology – mapping sensor specifications, drawing of the area being mapped (including racking, heating and cooling components, existing temperature sensors), acceptance criteria, and mapping locations.  Mapping sensors should be arranged in a grid fashion along the width and length of the area so that the area is reasonably covered with sensors located every 5-10 meters (20-30 meters for very large facilities).  At each point in the grid, sensors should be placed at high, medium, and low levels (or bottom, multiple middle, and top locations for tall areas).  Mapping should be run for a minimum of 7 consecutive days for warehouse and ambient storage areas and for between 24 and 72 hours for freezer rooms and cold rooms to    include operation of duplicate refrigeration units running separately.
  • Mapping report template – include introduction, summary, conclusions and recommendations
  • Annexes as needed – raw data, graphs, deviation reports/CAPAs, mapping sensor calibration certificates.

Most, if not all, of the above items would be provided in a typical validation protocol for a mapping study.  Often the protocol and report formats are “as specified” by the customer.  However, if the facility is subject to/ or may be inspected by organizations following the WHO supplement, ensuring these elements are included at the start of the study may eliminate questions during an inspection.

Have a need for or questions about mapping studies? Neil Enlow is Performance Validation’s responsible manager for this service. Temperature Mapping is one of Performance Validation’s core areas of expertise. In the last 20 years, we have executed hundreds of mapping studies, covering all spectrums of size and ranges, from cryogenic storage freezers to depyrogenation tunnels, from reach-in chambers to warehouses. PV owns and maintains a large inventory of calibrated and validated mapping equipment, including Vaisala VL-2000, VL-1000, VL-1416 data loggers, and Kaye Validator systems and we also have experience with most other temperature monitoring systems used within the industry (i.e. Ellab, Hobo, TempTales, Kaye AVS, Kaye ValProbes, etc.).

Source: WHO Technical Report Series, No. 992, Annex 5, Supplement 8

For Additional information please contact

Neil Enlow
Principal Validation Engineer
Performance Validation, LLC

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