Troubleshooting temperature mapping in a GxP distribution environment

Temperature mapping is a critical aspect of Good Distribution Practices (GDP), ensuring that pharmaceutical and medical products are stored within safe temperature ranges. However, not all distribution centers operate under the same controlled conditions as pharmaceutical manufacturing facilities. This reality often leads to complex questions about mapping methodologies, validation requirements, and monitoring strategies. During our recent Mapping Webinar, a manager overseeing temperature mapping at a distribution center raised key concerns about managing lost data loggers and mapping in an environment with limited temperature control. 

Lost Data Loggers During Mapping

One of the primary concerns raised was whether an area needs to be remapped if a data logger is lost during the process, especially when no failure criteria are outlined in the protocol. Remapping is not necessarily required but this depends on the Quality Management System (QMS) of the distribution center, as well as other policies and procedures (SOPs). The first step should be consulting the Quality Assurance (QA) team to assess whether the missing data significantly impacts the study’s validity.

Key considerations when a logger gets lost

•    What was the total number of data loggers used initially? If the study had a high density of loggers, losing one may not compromise the conclusions.

•    That said, if the logger density was minimal, it might be harder to argue that the lost data does not impact the study’s integrity.

•    Will you be able to justify the missing data through a deviation process? You will need to document a defense of why the remaining data is still sufficient.

Mapping in heat-only environments

How valid is a mapping study in a facility with only heat control? The question includes the possibility of heaters requiring Installation Qualification (IQ), Operational Qualification (OQ), and Performance Qualification (PQ) before mapping.
This shows the practical limitations faced by many distribution centers. Unlike pharmaceutical manufacturing sites, distributors often operate with centralized quality oversight and constrained validation budgets. This leads to variations in environmental control and mapping approaches.

Key considerations for minimal climate control:

•    Terminology Matters: In uncontrolled environments (such as heat-only warehouses), the process is often referred to as “temperature profiling” rather than “temperature mapping.” This distinction, drawn from USP 1079 guidelines, recognizes that while mapping is still valuable, the lack of control in a typical HVAC system means it serves a different purpose.
•    Value of Temperature Profiling: Even without IQ/OQ/PQ-validated heating systems, temperature profiling remains useful. It provides valuable data on how the environment behaves, identifies potential risk areas, and informs decisions about monitoring placement.
•    Compensating for Lack of Control: Since these spaces are less regulated, organizations should consider increasing the number of monitoring probes to capture more detailed temperature variations over time.

Practical strategies for monitoring an uncontrolled space

Even in a regulated warehouse, there is often a lack of standardized validation and the minimal number of loggers available for mapping studies. We have seen a 168,000-square-foot warehouse application that used only eight loggers, with inconsistent placement strategies for mapping. 

A structured approach to improving monitoring strategy:
1. Temperature Profiling First: Conduct a temperature profiling study to assess the warehouse’s ability to maintain required specifications. Use this data to identify hot and cold spots.

2. Strategic Probe Placement: Unlike a controlled facility where hot and cold spots may be less critical, in an uncontrolled space, monitoring should prioritize these areas to detect fluctuations.

3. Increasing Sensor Density: While it may not be necessary to use the same number of loggers for routine monitoring as for mapping, a higher density of probes can mitigate risks and provide a clearer picture of temperature variations.

4. Developing a Placement Rationale: Since there is no strict standard for data logger placement, organizations should adopt a logical approach. One suggested method is ensuring that no product is more than a set distance (e.g., 10 meters) from a monitoring probe. This approach helps establish a documented policy that can withstand audits.

Challenges are not deal-breakers

As shown, there are nuanced challenges of temperature mapping in distribution settings, particularly those with minimal environmental controls. While full validation (IQ/OQ/PQ) may not always be feasible, temperature profiling remains a valuable tool to understand environmental conditions and implement effective monitoring strategies.

By increasing sensor density, strategically placing loggers, and documenting rationale for monitoring approaches, distribution centers can enhance compliance with GDP requirements while operating within practical constraints. Ultimately, the goal is to ensure product integrity by making informed, risk-based decisions tailored to the realities of the distribution industry.
 

For further insights or support on temperature mapping and monitoring best practices, contact us.