Last Updated on December 23, 2025 by Melissa Lazaro

What Actually Changed and Why It Matters to PT Providers

If you’ve been running your proficiency-testing schemes for a while, chances are your system still traces back to ISO/IEC 17043:2010. That’s not unusual. I see it all the time.

Here’s the problem. Accreditation bodies are no longer assessing with a “2010 mindset.” Even when they’re flexible on transition timelines, their expectations already reflect the 2023 edition.

In my experience working with PT providers preparing for surveillance and transition audits, most surprises don’t come from brand-new requirements. They come from stronger expectations around things that already existed, but weren’t enforced as tightly before.

This article walks you through the real differences between ISO/IEC 17043:2010 and 2023, focusing on what auditors now look for, where PT providers get caught out, and how to adjust without rebuilding your entire system.

Structural & Terminology Changes in ISO/IEC 17043:2023 vs 2010

At first glance, the structure feels familiar. That’s intentional. The 2023 revision isn’t a rewrite from scratch.

What’s changed is the clarity and alignment.

The newer version aligns more closely with other conformity-assessment standards. That means clearer separation between:

• governance and impartiality,
• operational processes, and
• management system controls.

Here’s what I’ve noticed in audits. Even small wording changes now carry more weight. Terms like scheme design, performance evaluation, and responsibility for subcontracted activities are used more precisely. Auditors expect your procedures, forms, and reports to use the same language.

A common mistake I see is updating the quality manual but leaving participant instructions and statistical reports untouched. Auditors don’t miss that.

Pro tip: If a term appears in the standard, it should appear consistently in your documentation. Don’t let legacy wording quietly undermine your transition.

Risk-Based Thinking & Impartiality – Stronger in ISO/IEC 17043:2023

Risk-based thinking existed in 2010. Let’s be honest, though. Many PT providers treated it as a formality.

That no longer works.

In the 2023 version, risk is clearly tied to impartiality, validity of results, confidentiality, and scheme credibility. And auditors now expect risks to be identified where the work actually happens—not just in a management review slide.

I’ve seen providers flagged because they didn’t consider risks linked to:

• sample preparation done by related organizations,
• subcontracted laboratories with commercial ties,
• or statistical decisions made by a single individual without review.

This is important because PT credibility lives and dies on trust.

What works well in practice:
A simple, scheme-focused risk register that’s reviewed during scheme planning. No complex matrices. Just clear risks, controls, and responsibility.

What doesn’t:
A generic ISO 9001 risk log that never mentions PT activities.

Resource & Competence Requirements – What Changed from 2010 to 2023

Competence is one of the areas where auditors have clearly raised the bar.

Under ISO/IEC 17043:2010, qualifications and experience were often enough. Under the 2023 version, that’s just the starting point.

Now, competence means:

• defined criteria,
• ongoing evaluation,
• and evidence that people remain capable of doing their role.

This applies not only to internal staff, but also to subcontractors.

One real example I see often: a PT provider assumes that using an ISO/IEC 17025-accredited lab automatically satisfies all requirements. It doesn’t. You’re still responsible for ensuring their work fits your scheme objectives.

Pro tip:
Auditors love simple competence matrices linked directly to roles—scheme coordinator, statistician, technical reviewer. Keep it practical. Keep it current.

Process Requirements – PT Scheme Design, Data Handling & Reporting

This is where the 2023 version really tightens expectations.

Scheme design now needs to show a clear line of sight from:

• objectives,
• to measurands,
• to evaluation criteria,
• to how results are reported and interpreted.

I’ve reviewed PT reports where the statistics were technically correct, but the report never explained what participant performance actually meant. That’s a problem now.

Auditors expect transparency. They want to see why a statistical method was chosen and whether it fits the scheme purpose.

Common pitfall:
Copy-pasting statistical approaches from previous rounds without reassessing suitability.

What works:
Brief justifications written in plain language. You don’t need a statistics textbook. You need clarity.

Management System Changes – Option A & Option B in ISO/IEC 17043:2023

The Option A and Option B structure hasn’t disappeared, but expectations around it have sharpened.

If you claim Option B, auditors expect real integration. Not just a statement saying “we comply with ISO 9001.”

I’ve seen PT providers challenged because their ISO 9001 system didn’t actually control:

• scheme planning,
• result review,
• or corrective actions specific to PT activities.

For smaller providers, Option A is often the safer and simpler route. It allows you to tailor controls specifically to PT operations without forcing full system integration.

Key takeaway:
Choose the option that fits how you actually work—not the one that looks easier on paper.

Transition & Audit Focus – What Accreditation Bodies Emphasize Now

During recent surveillance and transition audits, assessors consistently focus on a few areas:

• risk and impartiality controls,
• competence evidence,
• consistency between scheme design, execution, and reporting.

Here’s something many providers don’t expect. Even when accreditation bodies allow phased transition, they still raise “soft findings” against 2023 expectations.

That’s often a warning shot.

Pro tip:
Prepare transition evidence early. Show assessors you understand the changes and are actively addressing them—even if implementation isn’t fully complete yet.

FAQs – ISO/IEC 17043:2023 vs 2010

Is ISO/IEC 17043:2023 a complete rewrite?
No. It’s an evolution. The core principles remain, but expectations are clearer and more consistently enforced.

Do all PT schemes need redesigning?
Not necessarily. Many schemes only need better justification and documentation, not full redesign.

When will accreditation bodies enforce the 2023 version fully?
Most already are, especially during surveillance. Transition grace periods don’t mean relaxed expectations.

Conclusion – What PT Providers Should Do Next

If there’s one thing to remember, it’s this: ISO/IEC 17043:2023 doesn’t demand more paperwork. It demands clearer thinking and stronger evidence.

From risk management to competence and reporting, the standard pushes PT providers to show how their decisions protect scheme credibility.

Based on what I see in real audits, the smartest next step is a focused gap review—looking specifically at where 2010-style practices no longer hold up.

Handled early, the transition is manageable. Left too late, it becomes stressful and expensive.

If you’re preparing for surveillance or transition, now is the right time to align—not after the auditor points it out.