NATA Assessment Preparation: A Step-by-Step Guide for Lab Managers

A NATA assessment is an audit of your laboratory's technical competence and quality management system against ISO/IEC 17025 (for testing and calibration labs) or ISO/IEC 17020 (for inspection bodies). Assessors are typically technical experts in your field — they know what good practice looks like, and they know where shortcuts are usually taken.

The labs that sail through assessments don't have fewer problems than other labs. They have better systems — systems where the records are already in order rather than assembled in a panic the week before the assessor arrives.

What NATA Assessors Actually Look For

NATA assessments cover two categories: technical requirements and management system requirements. The most common findings appear in these areas:

• Equipment calibration — instruments overdue for calibration, calibration certificates that don't include uncertainty, reference standards not traceable to national standards
• Document control — outdated procedures in circulation, SOPs without approval records, test methods referenced by name but no controlled copy available
• Personnel competency — training records incomplete, authorisation matrix not current, expired certifications for technical staff
• Measurement uncertainty — uncertainty budgets missing or not applied to reported results
• Internal audit — audits not completed at required frequency, findings not closed out with documented corrective actions
• Proficiency testing — participation below required frequency, unsatisfactory results not investigated with formal CAPA

For a deeper breakdown of each category, see our guide to the top 5 laboratory assessment non-conformances.

Three Months Before: Get Your Systems in Order

If your NATA assessment is three months away, the highest priority is getting your calibration and document control records into a state where they can be retrieved instantly.

Calibration: Pull every instrument's calibration record. Check the due date, check that the certificate includes uncertainty, and check that the issuing laboratory is NATA-accredited (or can demonstrate equivalent competence). Any overdue instruments should be sent for calibration immediately — don't wait.

Document control: Identify every controlled document (test procedures, SOPs, quality manual, work instructions) and confirm the current revision is the one actually in use. Obsolete versions should be withdrawn from circulation and archived. Approval records should exist for every current document.

Personnel: Check every technical staff member's qualification and authorisation records. Confirm that your authorisation matrix matches what people are actually doing. Flag any certifications expiring in the next six months.

One Month Before: Close Out Open Items

One month out, your focus should shift to closing open corrective actions, verifying your internal audit schedule is current, and confirming proficiency testing participation is documented.

Corrective actions: Any open CAR (Corrective Action Request) from a previous assessment or internal audit needs to be closed with objective evidence before the assessor arrives. An open CAR with no progress is a finding in itself. Your CAPA register should show every item's current status at a glance.

Internal audit: If your internal audit is overdue, conduct it now — even a partial audit covering high-risk clauses is better than an audit that hasn't happened at all. Document the findings and any corrective actions raised.

Proficiency testing: Confirm that PT results from the past assessment period are on file, that satisfactory results are documented, and that any unsatisfactory results have a completed investigation with CAPA.

The Week Before: Prepare Your Document Package

NATA assessors will typically ask to see specific records during the assessment. Having these ready — retrievable in under two minutes — creates a confident impression and avoids the disruption of searching during the assessment:

1. Current calibration certificates for all in-scope instruments
2. Current revision of all test procedures and SOPs
3. Personnel authorisation matrix with supporting qualification records
4. Internal audit report from the most recent cycle, with findings and closure records
5. Proficiency testing participation records and results
6. Non-conformance and CAPA register showing current status of all items
7. Management review minutes from the most recent review

Labs using a purpose-built quality management system can pull all seven items from one platform in minutes. Labs managing records across spreadsheets and shared drives typically spend days assembling the same package.

On the Day: What to Expect

A typical NATA reassessment for a small to medium testing lab runs over one to two days. The assessor will conduct an opening meeting, review your document package, witness technical demonstrations of testing activities, interview technical staff, and close with a findings summary.

The witnessing phase is where technical findings appear — the assessor will observe an actual test being performed and check that the procedure matches what the technician does in practice. If there's a gap between your written procedure and your actual method, it will be visible here.

The most important preparation: Brief your technical staff. They should know which procedures to follow, where the documents are, and what to say if they deviate from a procedure (there should be a formal process for that). Staff who are surprised by the assessor's questions create more findings than any document gap.

After the Assessment: Managing Findings

Minor findings (observations) typically need to be closed within 90 days. Major findings (non-conformances) have shorter timescales and may require a follow-up assessment. Respond to all findings with documented corrective actions, root cause analysis, and objective evidence of closure — not just an email saying "we fixed it."

The labs that perform best at successive assessments use each assessment as a genuine improvement opportunity, not just a compliance exercise. Findings that are thoroughly investigated and corrected rarely reappear. Findings that are superficially addressed consistently do. Read our guide on automating laboratory quality management to see how to embed these controls into daily operations.