In 35 years of working inside life sciences organizations, I have seen a lot of things get lumped together that should not be. One of the most common, and one of the most consequential, is calibration and preventive maintenance. They are related in the sense that both are part of a sound equipment management program. But they are not the same thing, they do not serve the same purpose, and confusing the two tends to create problems that are entirely avoidable.
This is worth getting right.
What Maintenance Is
By the book, preventive maintenance is the scheduled, proactive servicing of equipment to keep it functioning reliably. It includes cleaning, lubrication, part replacement, and inspection activities designed to prevent failure before it occurs. At its core, maintenance it’s about mechanical reliability. It asks the question: “Is this equipment running?”
A well-executed maintenance program extends equipment life, reduces unplanned downtime, and protects capital investment. In a regulated environment, it’s also a GMP requirement. But maintenance alone does not tell you whether the equipment is providing accurate, trustworthy data. That is a different question entirely.
What Calibration Is
Calibration (again, by the book) is the process of comparing an instrument’s output against a known, traceable standard and documenting the result. It asks a different question than maintenance does: “Is this equipment measuring correctly?”
In a regulated life sciences environment, the answer to that question has direct implications for product quality, patient safety, and regulatory standing. A pH meter that reads 7.1 when the actual value is 6.8 is not just inaccurate. It is a data integrity problem. A temperature sensor that drifts outside its acceptable range may have been generating suspect data for weeks or months before anyone noticed. The product released during that window does not get recalled because the maintenance was overdue. It gets recalled because the measurements cannot be trusted.
That is the distinction that matters.
Where Organizations Get Into Trouble
The most common pattern I see is organizations that maintain their equipment rigorously but treat calibration as an afterthought. Calibrations are scheduled, delayed, and rescheduled. Instruments drift out of tolerance and stay there longer than they should because the calibration program lacks the structure and oversight to catch it. And when an audit or an investigation surfaces the gap, the organization is left trying to assess the impact of out-of-tolerance conditions on product that has already left the facility.
That’s a very uncomfortable position to be in. And it’s entirely preventable.
The other pattern is organizations that outsource calibration to whoever is available rather than building a consistent, program-level relationship with a qualified provider. Calibration performed by a rotating cast of vendors, with inconsistent documentation and no institutional knowledge of the instruments in question, is technically calibration. But it’s not a calibration program. And regulators know the difference.
What Good Calibration Program Management Looks Like
A sound calibration program starts with a complete, accurate inventory of every instrument and piece of equipment subject to calibration requirements. It assigns calibration intervals based on how much you are relying on that instrument to get it right, manufacturer recommendations, historical performance, and regulatory requirements. It tracks due dates proactively rather than reactively. And it generates clean, complete, and traceable documentation to recognized standards.
When an instrument is found out of tolerance, a good program has a defined process for assessing impact, initiating the appropriate documentation, and determining whether product or data generated during the out-of-tolerance period is affected. That process should not be invented on the fly during an investigation. It should already exist.
At Krieger, our calibration work is built around exactly this kind of program-level thinking. We are not there to show up, calibrate a list of instruments, and leave. We are there to understand your environment, your instrumentation, your risk profile, and your regulatory obligations, and to build a calibration program that holds up under scrutiny because it was designed to.
That ongoing relationship is what turns calibration from a line item into a genuine compliance asset.
The Bottom Line
Maintenance keeps your equipment running. Calibration keeps your data trustworthy. Both matter. But they are not interchangeable, and a program that excels at one while neglecting the other is not a compliant program. It is a program with a gap.
In life sciences, gaps have consequences. The good news is that this particular gap is one of the most straightforward to close, with the right partner and the right approach.
