NABL Accreditation Process for Laboratories: Step-by-Step Guide

NABL — the National Accreditation Board for Testing and Calibration Laboratories, a constituent board of the Quality Council of India — is the accreditation body for laboratories in India. NABL accreditation tells customers, courts, regulators and doctors that a laboratory is competent to produce valid results for a defined scope.

This guide walks through the process as it works today, and what a laboratory should have in place before it applies.

Step 0: Which standard applies to you?

Most laboratories reading this will fall under ISO/IEC 17025 or ISO 15189.

Step 1: Decide your scope

Accreditation is granted for a scope: the specific tests, calibrations or examinations, the methods used, and their ranges. Start with work that is stable, frequent and important to your customers. You can extend the scope later.

Step 2: Gap assessment

Compare current practice with the standard and NABL's specific criteria for your field. Typical gaps include missing method validation, no measurement uncertainty estimates, calibration certificates without valid traceability, incomplete training and authorisation records, and no plan for proficiency testing.

Step 3: Build the management system and technical records

• Quality manual and procedures
• Method SOPs, with verification of standard methods and validation of in-house or modified methods
• Measurement uncertainty estimates where required
• Equipment register, calibration programme and intermediate checks
• Staff qualifications, training, competence assessment and authorisation
• Internal quality control and reporting formats

Step 4: Proficiency testing

Participate in proficiency testing (PT) or external quality assessment (EQAS) for the tests in your scope, preferably from accredited PT providers. Where no scheme exists, arrange inter-laboratory comparisons. Investigate any unsatisfactory result and record the corrective action.

Step 5: Internal audit and management review

Before applying, run at least one complete internal audit against the standard and a management review. Assessors will look at both.

Step 6: Apply on the NABL portal

Applications are made online through NABL's portal (linked from nabl-india.org), with the scope, documents and fees as specified in NABL's current documents.

Step 7: Assessment

NABL reviews the documents and appoints an assessment team — a lead assessor and technical assessors for your disciplines. The on-site assessment covers the management system and witnesses actual tests or calibrations. Findings are raised as nonconformities.

Step 8: Corrective action and decision

The laboratory submits evidence of corrective action for each nonconformity within the time allowed. NABL then makes the accreditation decision for the recommended scope.

Step 9: Surveillance and reassessment

Since October 2024 NABL operates a four-year accreditation cycle, with yearly on-site surveillance and reassessment every two years. Accredited laboratories must keep PT participation, internal audits and management reviews going throughout the cycle.

How long does it take?

Preparation usually takes 6 to 12 months, depending on the scope and how much of the system already exists, followed by NABL's own processing and assessment time. The most common causes of delay are incomplete validation, missing PT results and records that don't match actual practice.

Common mistakes to avoid

• Writing a quality manual that doesn't reflect how the laboratory really works
• Applying for too wide a scope in the first round
• Using equipment whose calibration certificates lack valid traceability
• Leaving PT and internal audit until just before the application
• Treating accreditation as a one-time event instead of an ongoing system

How Certsure helps

Certsure is a Lucknow-based consultancy. We help laboratories define their scope, close gaps, prepare documentation, plan validation and PT, train staff and get ready for assessment. Accreditation itself is granted only by NABL.

• NABL for testing, calibration and forensic laboratories (ISO/IEC 17025) →
• NABL for medical laboratories (ISO 15189) →
• Forensic laboratories: ISO/IEC 17025 requirements for forensic science laboratories