What to Look for in an Accredited Calibration Provider

When accuracy and reliability matter, choosing the right calibration provider is critical. But navigating the world of calibration services can get complicated fast. From accreditation and NIST traceability to industry-specific standards and measurement uncertainty, there’s a lot to consider.

Accredited vs. Non-Accredited Labs: What’s the Difference?

Not all calibration labs are created equal. An accredited calibration lab has been thoroughly evaluated by a recognized third-party accreditation body—such as A2LA or NVLAP—to ensure technical competence and compliance with international standards like ISO/IEC 17025.

These evaluations cover everything from the lab’s equipment and personnel to procedures and quality systems. Choosing an accredited lab gives you confidence that the work meets rigorous, internationally recognized benchmarks.

However, accreditation doesn’t automatically mean a lab meets your specific needs. Accreditation confirms the lab is capable of performing calibrations to certain standards—but it's up to you to determine whether those standards align with your equipment, industry, and application.

The Role of Industry-Specific Standards

Different industries often have their own calibration requirements. Organizations like ASME (American Society of Mechanical Engineers) and ASTM (American Society for Testing and Materials) publish detailed standards for specific equipment.

For example, SME B40.1 offers guidance for pressure gauge calibration, while ASTM E2655 covers calibration for thermocouples.

Partnering with a lab that understands and adheres to your industry’s standards ensures your calibration results will meet the demands of your field.

What Is NIST Traceability—And Why Does It Matter?

NIST traceability refers to the ability to trace a measurement back to the national standards maintained by the National Institute of Standards and Technology (NIST) through an unbroken chain of comparisons.

It’s important to understand that not all accredited calibrations are automatically NIST-traceable. Whether NIST traceability is required depends on your specific application and industry requirements.

As Joe Moser, CEO of Accredited Labs, explains:

“At Accredited Labs, we offer both accredited and NIST-traceable calibrations to meet the diverse needs of our clients. Our accredited calibrations provide the highest level of assurance in terms of technical competence and quality management. But we also understand that not every situation calls for accreditation. That’s why we also offer high-quality, NIST-traceable calibrations backed by our commitment to excellence.”

Understanding CMC: Calibration and Measurement Capability

Another key factor in selecting a provider is the lab’s Calibration and Measurement Capability (CMC)—essentially, the smallest measurement uncertainty the lab can achieve for a given calibration.

Why does that matter? A lower CMC is ideal for applications requiring tight tolerances. On the other hand, a higher CMC may be acceptable for less critical measurements.

Example: A company manufacturing aerospace components may need extremely precise calibrations with minimal uncertainty. In that case, they would seek out an accredited lab with a proven track record and a low CMC specific to their equipment.

Choosing a Partner You Can Trust

When evaluating calibration providers, don’t stop at accreditation. Look for a lab that:

• Follows relevant industry-specific standards
• Offers calibrations with the appropriate CMC for your application
• Provides NIST traceability when required
• Demonstrates a clear commitment to quality and customer service

At Accredited Labs, we’re proud to offer both accredited and NIST-traceable calibrations tailored to the diverse needs of our clients across industries. Our skilled technicians and metrologists stay current with the latest standards and best practices, so you can trust that your equipment is in expert hands.

“We pride ourselves on our ability to provide both accredited and NIST-traceable calibrations to meet the diverse needs of our clients across industries. Our team of experienced technicians and metrologists works diligently to stay up-to-date with the latest industry standards and best practices, ensuring that our calibration services consistently exceed expectations.”

— Aaron Aldinger, Senior Advisor