Last Updated on September 24, 2025 by Melissa Lazaro

How to Apply for ISO 15189 2022 Accreditation—Step-by-Step Process Explained

Let’s be real—getting started with ISO 15189:2022 accreditation can feel overwhelming. I’ve had lab managers sit across from me, completely confident in their technical team, but totally unsure where to even begin with the application process.

They ask things like:
“Do we need to finish everything before we apply?”
“What documents do we actually submit?”
“How do we avoid failing the audit?”

In my experience guiding over 60 labs through this exact journey, I’ve noticed one thing: the labs that succeed aren’t necessarily the biggest or best funded—they’re the ones that understand the process, step-by-step, and prepare smart.

So in this article, I’m breaking it all down for you. No fluff, no vague advice.

Here’s what you’ll get:

• A clear, practical roadmap for applying for ISO 15189:2022

• What to expect at each stage—from gap assessment to audit

• Common missteps to avoid (based on real stories)

• Pro-level tips that’ll save you time, money, and a lot of back-and-forth with the accreditor

If you’re serious about getting accredited—and want to do it right the first time—this guide is for you. Let’s get started.

Understanding the ISO 15189:2022 Accreditation Process

Before we get into the step-by-step details, let’s zoom out for a second.

Because here’s what I’ve noticed—most labs think ISO 15189 is just about getting a certificate. But it’s really about building a quality system that proves your lab is technically competent, reliable, and globally recognized. Accreditation is simply the process that validates that.

So what does that process actually look like?

Here’s the big picture:

1. You prepare internally by aligning your systems with ISO 15189:2022.

2. You choose an accreditation body—this is the independent organization that assesses your lab.

3. You submit your application with documentation showing that you’re ready.

4. An on-site assessment is conducted to see how things really work inside your lab.

5. You respond to any findings, and once they’re cleared—you get accredited.

Sounds simple on paper, right? But each of those steps includes layers of work: document preparation, staff training, audits, reviews, and a whole lot of coordination.

Who Gives You the Accreditation?

That part often confuses people too. You don’t get accredited by ISO. You get accredited by a national or regional accreditation body—and not just any body. You want one that’s recognized by ILAC (the International Laboratory Accreditation Cooperation), which ensures your accreditation is globally accepted.

Examples include:

• UKAS (United Kingdom)

• NABL (India)

• SANAS (South Africa)

• A2LA or ANAB (USA)

• COFRAC (France)

These bodies follow internationally agreed rules and are evaluated regularly. If your lab wants to be trusted across borders, choose a body that’s ILAC MRA-recognized.

Step 1: Do a Gap Assessment Before You Even Think About Applying

Let’s start with the most overlooked—and most important—step in the entire process.

Here’s what I’ve noticed:

Labs often jump straight into documentation or try to rush toward the application because they’re eager to “get certified.” But without knowing where you stand right now, you’re flying blind. And that’s how delays, rework, and failed audits happen.

So what exactly is a gap assessment?

It’s a deep, honest look at your current operations compared to what ISO 15189:2022 requires. You’re basically asking:

• What are we already doing well?

• What’s missing?

• What’s outdated?

• What needs improvement before an auditor walks in?

It’s not just about documents—it’s about people, processes, risk management, competence, and control. The 2022 revision especially emphasizes risk-based thinking and process-driven management, so if your current system is reactive or overly siloed, you’ll need to rework some foundations.

What should your gap assessment cover?

At minimum, you’ll want to review:

• Documented procedures and how well they match real practice

• Training and competency records for all testing staff

• Equipment calibration, maintenance, and traceability

• How you manage nonconformities, complaints, and risk

• Internal audit readiness and past performance

• Whether you’ve already built in the updates from the 2022 version

DIY vs. Getting Help

You can run a gap assessment internally if your team has experience with ISO 15189:2022. But if you’re new to it—or transitioning from an older version—it’s often worth getting outside support.

In my experience, a well-run gap assessment saves weeks, if not months, down the line. It gives you a realistic project plan, avoids scope creep, and prevents nasty surprises during the actual assessment.

Real story: One lab I worked with thought they were ready to apply. After a quick 5-day gap check, we uncovered 32 critical gaps—including missing internal audit records and incomplete risk registers. They avoided what would’ve been a failed audit—and we got them ready in 8 weeks instead.

Step 2: Build or Update Your Quality Management System (QMS)

Now that you’ve done your gap assessment and know what needs fixing, it’s time to get your QMS in shape.

And let me be clear: this isn’t just about paperwork. Your QMS is the backbone of your lab’s operations—it shows how you manage quality, minimize risk, ensure accurate results, and handle problems when things go wrong.

Here’s what you need to cover (and prove):

• A clear and functional Quality Manual

• Documented standard operating procedures (SOPs) for every process that affects test quality

• Up-to-date staff training and competency records

• Document control procedures (so old versions don’t sneak back in)

• Records of equipment calibration and maintenance

• Defined procedures for internal audits, risk management, and management review

• A process for handling nonconformities, complaints, and corrective actions

ISO 15189:2022 added more emphasis on risk-based thinking, evidence of staff competence, and integration of quality across departments—not just in the lab manager’s office. So your QMS can’t be theoretical. It has to be lived.

Templates help—but only if you adapt them

A lot of labs ask me, “Can’t we just use a QMS template?” And yes, templates can be a huge time-saver—as long as you treat them like a starting point.

Here’s the problem I see all the time: labs copy and paste policies that sound good, but don’t match what their staff actually do. Then the auditors show up, ask a tech how a test is verified, and the answers don’t line up. That’s a red flag—and it almost always leads to findings.

You don’t need to reinvent the wheel. But make sure the documents reflect your reality—not just what’s on paper.

How long should this take?

If you’re starting from scratch, building a QMS can take 2 to 4 months, depending on your resources and how committed your team is. If you already have ISO 9001 or an older version of ISO 15189 in place, and your system is solid, you might only need 4 to 6 weeks to align with the 2022 updates.

Step 3: Run Internal Audits and a Management Review Before You Apply

This is the point where a lot of labs think, “We’ve got the documents done—let’s apply!”

But hold on.

You’re not ready to submit anything until you’ve actually tested your system through internal audits and reviewed how it’s performing at the management level.

Why this step matters (a lot)

ISO 15189:2022 isn’t just about having a documented system—it’s about showing that your system works in real life. Auditors will ask:

• Have you run a full internal audit cycle?

• Did your management team review the system’s performance?

• What were the findings?

• What actions did you take to improve?

If you haven’t done this—and can’t prove it—you’re not ready to apply.

Internal audits: your lab’s dress rehearsal

An internal audit isn’t just a checklist exercise. It’s your chance to catch issues before the real auditors do. That means reviewing:

• Whether your procedures are being followed in practice

• If your records are up to date and traceable

• Whether staff know their roles and responsibilities

• How well you manage risk, quality control, and improvement

You’ll also need to document findings and implement corrective actions—not just identify problems.

What I’ve seen work well: One lab I supported ran a full internal audit across three departments using a rotating schedule. Each team audited the next. They caught 12 issues—including outdated forms and gaps in training records—and fixed them before the external audit. No major findings during the real assessment.

Management review: where leadership takes ownership

This part shows that your leadership is actually involved in quality—not just rubber-stamping forms.

Topics to cover:

• Audit results

• Customer or clinician feedback

• Staff competence and training

• Risk and opportunity review

• Quality objectives and their progress

• Any incidents, complaints, or nonconformities

Document it. Discuss it. Act on it. That’s what auditors want to see.

Timing tip:

Make sure your internal audit and management review are completed before you submit your application. Most accrediting bodies require this as part of the readiness documentation—and if it’s missing, they’ll push your audit back.

Step 4: Submit Your Application to the Accreditation Body

Now that your system is built, tested, and reviewed—you’re finally ready to apply. But what does that actually involve?

Here’s what I tell every lab I work with: applying for ISO 15189:2022 is more than just filling out a form. It’s about presenting proof that your lab is ready to be assessed. That means documents, records, and a clear understanding of your scope.

Let’s walk through how to do it right.

Choose the Right Accreditation Body (It Matters)

Start by selecting an accreditation body that:

• Is recognized by ILAC (International Laboratory Accreditation Cooperation)

• Is accepted by your national health authority or regulators

• Offers ISO 15189:2022 assessments specifically for medical labs

Examples include:

• UKAS – United Kingdom

• NABL – India

• SANAS – South Africa

• A2LA or ANAB – United States

• COFRAC – France

Pro tip: If your lab plans to work internationally—or export results—make sure the accreditor is part of the ILAC Mutual Recognition Arrangement (MRA). That ensures your accreditation will be accepted globally.

Prepare the Required Documents

Most accreditation bodies will ask for:

• Your completed application form

• A copy of your quality manual

• A list of your SOPs and controlled documents

• Evidence of your internal audits and management review

• Your defined scope of accreditation (tests, methods, and equipment)

• Staff lists, training records, and key roles

Some will also ask for a copy of your organization chart, details on IT systems, or recent proficiency testing results.

What Happens After You Submit?

Once submitted, the accreditor will:

1. Review your documentation

2. Ask for clarifications or corrections, if needed

3. Assign a team of assessors based on your lab’s scope

4. Schedule the on-site assessment—or offer a pre-assessment first (recommended if this is your first time)

Heads up: Scheduling can take anywhere from 4 to 12 weeks, depending on the accreditor’s availability. That’s why I always suggest reaching out early—before you’ve finalized all your documents—just to get into the queue.

Step 5: Prepare for and Undergo the On-Site Assessment

Okay, now the real test begins.

Once your application is accepted and your audit is scheduled, your lab will go through an on-site assessment. This is where the accreditation body sends qualified assessors to evaluate whether your quality system works not just on paper—but in practice.

What Actually Happens During the Assessment?

Think of it as a multi-layered inspection. Assessors will:

• Review your documents and records

• Observe your staff performing actual tests

• Interview your team about their roles, procedures, and decision-making

• Check equipment calibration and maintenance logs

• Look at sample handling, traceability, and data integrity

• Verify how you manage nonconformities, incidents, and risks

They’re not there to play “gotcha”—they’re there to confirm you’ve built a system that works, is followed, and aligns with ISO 15189:2022 requirements.

How to Prepare Your Team

This is where a lot of good labs fall short. The documents are perfect, but the staff are nervous or unsure when asked questions during the audit.

Here’s what I recommend:

• Run a mock audit a few weeks before the real thing

• Coach staff on key areas like sample handling, equipment use, and reporting

• Practice answering auditor questions like:

  • “How do you know your test method is valid?”

  • “What do you do if there’s a QC failure?”

  • “Where are the latest SOPs kept, and how do you know they’re current?”

Real insight: One lab I worked with held short daily “audit warm-ups” for two weeks before the assessment. Just 15 minutes a day reviewing key processes. When the audit came, their staff answered confidently—and they had zero major findings.

Should You Do a Pre-Assessment?

If this is your first ISO 15189 accreditation—or your first upgrade to the 2022 version—yes.

A pre-assessment is like a test run. It’s informal, doesn’t result in findings on your official record, and helps you fix weak spots before the real audit. Many labs who skip this step end up regretting it.

After the Assessment

You won’t get your certificate right away. After the audit, you’ll receive:

• A report summarizing what the assessors found

• A list of any nonconformities (minor or major)

• A deadline (usually 30–90 days) to respond with corrective actions

That leads us to the final step—what to do after the audit, how to respond to findings, and how to wrap things up. Let’s finish strong.

Step 6: Respond to Findings and Finalize Your Accreditation

So, the assessment is done. Your team did their part. Now what?

This is the phase where everything you’ve built comes together—or falls short. And here’s what I tell every lab at this stage: how you respond to findings is just as important as the audit itself.

First, Understand the Assessment Report

After the audit, you’ll receive a formal report. It typically includes:

• A summary of how your lab performed

• A list of any nonconformities (NCs), categorized as minor or major

• Comments and observations (sometimes just recommendations)

• A timeframe to address each finding (usually 30 to 90 days)

Don’t panic if you receive NCs—almost every lab gets some. What matters is how you handle them.

How to Respond Effectively

Each nonconformity requires:

1. A root cause analysis – Why did the issue happen?

2. A corrective action plan – What did you do to fix it?

3. Evidence – Documents, screenshots, photos, or records that prove your fix

What assessors want to see: That you’ve thought it through, corrected the root cause—not just the symptom—and that the fix is actually working.

Pro tip: Don’t send a generic response like, “We retrained staff.” That rarely satisfies an assessor on its own. Be specific: who, when, what materials, and how you’ll prevent it from happening again.

What Happens After That?

Once your responses are submitted, the accrediting body will:

• Review your evidence

• Possibly ask for clarification or more proof

• Issue a decision on your accreditation

If everything checks out, you’ll receive your official ISO 15189:2022 accreditation certificate. That means you’re now recognized as a competent, quality-driven medical lab—not just in your country, but anywhere your accrediting body is recognized through ILAC.

And Then?

You maintain it.

Accreditation isn’t a finish line—it’s the start of a continuous improvement cycle. You’ll have:

• Surveillance audits annually or every two years

• Full reassessment every 3–5 years

• Ongoing obligations to keep your system current, staff trained, and quality high

But don’t worry—we’ll cover how to manage that in a separate guide.

Pro Tips: What I Tell Every Lab Before They Apply for ISO 15189

After helping dozens of labs go through this process, I’ve seen what saves time—and what causes preventable delays. Here are some of my go-to tips that can make your accreditation journey a lot smoother.

PRO TIP 1: Start With a Gap Assessment—Even If You Think You’re Ready

I’ve seen too many labs say, “We already have most of this,” only to discover major gaps after applying. A solid gap check helps you fix issues early, avoid scope creep, and set a clear path to audit.

Think of it as your project’s blueprint. Without it, you’re guessing.

PRO TIP 2: Don’t Overlook Staff Readiness

You can have great documents, but if your team can’t explain what they do and why—it’ll show. Train your staff to confidently talk through procedures, equipment use, and their role in quality.

Auditors often say, “Your staff told the story better than your manual.” That’s a win.

PRO TIP 3: Use the Application Period to Stay Audit-Ready

Once you submit your application, don’t sit idle. Use that 4–8 week window to run mock audits, fix anything you’ve been postponing, and keep your team engaged. You want to be sharp when the audit team walks in.

INSIDER INSIGHT: Customize Your Templates

Templates save time, but they’re only helpful if they match your reality. Don’t submit procedures that no one in your lab follows. That’s one of the quickest ways to rack up findings.

PRO TIP 4: Treat the On-Site Audit Like a Conversation, Not an Interrogation

Your auditors aren’t there to “catch” you. They’re verifying how well your system works. Be honest, be clear, and treat it like a collaborative check—not a courtroom drama.

Common Mistakes to Avoid—And Your Top ISO 15189 Questions Answered

Let’s be real—most labs don’t mess up ISO 15189 accreditation because they don’t care. They mess up because they don’t know what’s coming. These are the most common slip-ups I see (even in well-run labs)—and the questions I hear the most from first-time applicants.

Common Mistakes That Set Labs Back

1. Applying Too Early
This one happens a lot. Labs finish their documents and rush to apply—without running internal audits or a management review. Most accreditation bodies will kick the application right back, or delay your assessment.

Slow down just enough to do it right the first time.

2. Copying Templates Without Customizing Them
I get it—templates save time. But if your procedures don’t reflect what your staff actually do, auditors will spot it immediately. That’s an easy way to get hit with nonconformities.

3. Assuming the Audit Is Just About Documents
Yes, paperwork matters—but auditors spend a lot of time talking to your team, watching how tests are performed, and checking equipment records. If your people aren’t prepared, your paperwork won’t save you.

4. Ignoring Risk-Based Thinking
ISO 15189:2022 expects labs to actively identify and manage risks. If you’re still treating risk as a paragraph in your quality manual instead of part of your daily work—you’ll get flagged.

Top Questions I Get From Labs About the Process

Q1: How long does the full application and accreditation process take?
A: From the start of your gap assessment to receiving your certificate, most labs take 6 to 12 months. That depends on your readiness, team availability, and how fast your accreditor can schedule the audit.

Q2: Can we apply without using a consultant?
A: Yes, but it may take longer—especially if your team hasn’t gone through ISO 15189 before. Many labs now use a hybrid model: toolkits + part-time consulting support. That gives you expert guidance without the full-time cost.

Q3: What if we fail the audit?
A: You probably won’t “fail”—but it’s common to get nonconformities. Most are minor and can be resolved within 30–90 days with corrective actions. The key is to respond clearly and thoroughly, with solid evidence.