Mapping Mistakes: Common GxP Temperature Mapping Errors and How to Avoid Them

Temperature mapping mistakes are more common than the pharmaceutical industry might like to admit, and many of them are preventable.

According to Stephanie Punter, GxP Team Lead and Projects, Deputy Quality for the Americas at ELPRO, the errors that derail mapping studies, create audit findings and compromise data integrity are rarely exotic. They tend to be the result of inadequate planning, unclear communication and documentation practices that fall short of GxP expectations.

Many of the most common mapping mistakes are preventable with good preparation and communication. Start by understanding the facility, the product requirements, and the potential temperature risks.

Stephanie Punter, GxP Team Lead & Projects, Deputy Quality for the Americas, ELPRO

The Most Common Temperature Mapping Mistakes in Pharma

When asked what mapping errors come up most frequently, Stephanie's answer is consistent with what auditors and quality teams encounter in the field: the problems are often straightforward, and that's exactly what makes them frustrating.

The most common mistakes include incorrect or incomplete documentation, data loggers being displaced or placed in the wrong locations, adjustments to HVAC temperature set points during the study without appropriate documentation, and approved protocols not being followed as written.

What surprises me is how frequently documentation-related issues occur. The mapping data itself may be perfectly usable, but poor or incomplete documentation can make it difficult to reconstruct exactly what happened during the study and assess the impact of any deviations.

Stephanie Punter, GxP Team Lead & Projects, Deputy Quality for the Americas, ELPRO

This is a critical point. A technically sound mapping study can be rendered unusable by documentation failures that prevent reviewers from understanding what actually took place. The data may be good; the record of how it was collected may not be.

Incorrect Sensor Placement: How It Happens and Why It Matters

One of the most consequential technical errors in a pharmaceutical storage mapping study is placing sensors in the wrong locations. When that happens, the study may not capture temperature conditions in the areas that matter most.

This can happen when floor plans are outdated or when facility layouts and logger locations are not clearly defined.

Stephanie Punter, GxP Team Lead & Projects, Deputy Quality for the Americas, ELPRO

The consequence is significant. Critical locations may be missed entirely, meaning the mapping data does not provide a complete picture of temperature distribution and associated risks within the facility. A study that fails to characterize the right areas cannot reliably inform SOP development, monitoring sensor placement, or risk management decisions. In effect, it leaves gaps in the foundational knowledge the storage operation is supposed to be built on.

When in the Process Do Mistakes Most Often Occur?

In any mapping study, the planning stage carries the highest risk.

During the planning stage, it is critical to ensure that facility layouts are accurate, teams are informed and appropriately trained, and roles and expectations are clearly understood. Consistent and clear communication before, during, and after the project is key to ensuring a successful mapping study.

Stephanie Punter, GxP Team Lead & Projects, Deputy Quality for the Americas, ELPRO

This matters because mistakes made in planning tend to compound. An inaccurate floor plan leads to incorrect logger placement. Poorly defined roles lead to protocol deviations that go undocumented. Inadequate training leads to documentation errors that an auditor will find almost immediately. By the time the study is complete, what began as a planning oversight has become a data integrity problem.

GxP Documentation Audit Failures: What Auditors Actually Find

In Stephanie's experience, the documentation errors that surface during GxP audits are not obscure or technical. They are often the kind of basic record-keeping failures that good training and clear expectations could prevent.

The framework she points to is ALCOA: records should be Attributable, Legible, Contemporaneous, Original (or a true copy) and Accurate. These principles are fundamental to GxP documentation, and yet audit findings frequently involve violations of one or more of them.

I see a lot of incomplete records, for example, tables with a 'Comments' section that has simply been left blank. I also see corrections where the original entry has been scribbled out and is no longer legible.

Stephanie Punter, GxP Team Lead & Projects, Deputy Quality for the Americas, ELPRO

Both are straightforward findings for an auditor to identify. Both are also straightforward to avoid. Every field in a mapping record should be completed appropriately, and any correction should be made in a way that preserves the original entry and maintains a clear, traceable record. Scribbling out an entry doesn't just look careless; it raises questions about what was being concealed, even when the answer is nothing.

Does a Flawed Study Need to Be Redone? It Depends on the Documentation

When a temperature mapping study goes wrong, the question of whether the data can still be used or whether the study needs to be repeated comes down to one thing: documentation quality.

Good documentation can often allow the data to remain usable. If a logger is placed in the wrong location but we know exactly where it was actually placed, the data may still be useful and can potentially be included in the study.

Stephanie Punter, GxP Team Lead & Projects, Deputy Quality for the Americas, ELPRO

The same principle applies to other mid-study deviations. If a temperature set point is changed during the study, but the record shows exactly when the change was made and what the new set point was, the data may still be evaluable. The key is having complete, accurate, and transparent documentation that allows reviewers to understand what happened and assess the impact.

The studies that cannot be salvaged are the ones where the documentation doesn't support that reconstruction. When the record of what happened is incomplete or ambiguous, the integrity of the data cannot be established, and the study needs to be repeated.

Mapping Data Misuse: Checking a Box vs. Building Knowledge

One of the more subtle but consequential mapping mistakes in pharma is not an error in execution but in intent. Stephanie sees many organizations conduct mapping studies simply to satisfy a compliance requirement, without extracting the operational value the data could provide.

Rather than viewing mapping as a simple pass/fail exercise, use the study to develop a deeper understanding of temperature distribution and identify temperature-related risks within your facility.

Stephanie Punter, GxP Team Lead & Projects, Deputy Quality for the Americas, ELPRO

Done well, a mapping study can optimize storage practices, determine the most appropriate locations for ongoing monitoring, and surface opportunities to reduce risk and improve operations. In some cases, it can identify issues with product preconditioning, door management, or air circulation that, once addressed, improve both compliance standing and day-to-day efficiency.

When used effectively, a mapping study can also identify opportunities to improve operations, reduce risk, and potentially save both time and money.

Stephanie Punter, GxP Team Lead & Projects, Deputy Quality for the Americas, ELPRO

Treating mapping as a checkbox misses all of that. It also means that when something goes wrong in storage, the organization may not have the foundational data to understand why.

After a Failed Audit: Determining What Went Wrong

When a pharmaceutical company comes to ELPRO following a failed audit or a problematic mapping study, Stephanie's approach is methodical. She begins by distinguishing between two different types of problems: execution failures and facility failures.

It is usually clear from the data whether an unsuccessful study is the result of incorrect study execution or an indication that the facility itself is not adequately controlled.

Stephanie Punter, GxP Team Lead & Projects, Deputy Quality for the Americas, ELPRO

A thorough review covers the testing that was performed, when and how it was conducted, the risks that were considered, and what the resulting data demonstrates. From there, the path forward depends on what the review reveals.

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