Nonconformity Management: Continuous Improvement and Corrective Actions in the Food & Agriculture Sector

1. What a nonconformity is in a testing laboratory

A nonconformity is any failure to meet a requirement. It can relate to an ISO 17025 requirement, an internal laboratory procedure, a client specification, or a regulatory requirement. Nonconformities are typically classified into two categories: those affecting the validity of results (nonconforming work) and those affecting the management system (system nonconformities).

Examples of nonconforming work in water testing laboratories

Accreditation scope: An analyst uses a method that is not included in the laboratory’s accredited scope (e.g., under UKAS, A2LA, or NELAP) to report a result under accreditation.

Equipment calibration: A piece of equipment is used outside its valid calibration interval.

Holding times: A sample is analyzed after its holding time has expired.

Certified reference material: A certified reference material result falls outside the acceptance limits, and the associated sample batch has already been reported without repeating the analysis.

Examples of system nonconformities

SOP review: A standard operating procedure (SOP) has not been reviewed by the scheduled review date.

Staff training records: A staff training record is incomplete.

Proficiency testing: An unsatisfactory proficiency testing result has not led to a documented corrective action.

Audit trail: The audit trail shows that a result was modified without a recorded justification.

2. The lifecycle of a nonconformity under ISO 17025

2.1 Detection and identification

Nonconformities can be detected through multiple channels: during quality-control (QA/QC) data review, during an internal audit, through a client complaint, during an accreditation assessment, or through periodic management-system reviews. A LIMS can automate detection in the first case: if a control result violates a Westgard rule, the system automatically generates an associated nonconformity.

2.2 Recording and classification

Every nonconformity must be recorded with a clear description of the failure, the detection date, the person responsible for the investigation, and a severity classification. Zendo LIMS allows nonconformity records to be linked to their specific context: the affected sample, the equipment involved, the method used, or the SOP that was breached. This contextual linkage is what separates a useful record from a mere administrative exercise.

2.3 Root Cause Analysis

ISO 17025 does not prescribe a specific root cause analysismethodology, but it does require that the root cause of the nonconformity be identified. The most commonly used tools in laboratories are the 5 Whys (for straightforward nonconformities), the Ishikawa or fishbone diagram (for nonconformities with multiple contributing factors), and 8D analysis (for serious nonconformities requiring a structured approach).

Zendo LIMS includes structured fields for documenting root cause analysis directly within the nonconformity record itself, preventing information from being scattered across external documents.

2.4 Corrective action

A corrective action is a measure implemented to eliminate the root cause of a nonconformity and prevent its recurrence. It should not be confused with a correction (an immediate action to mitigate the effect, such as withdrawing an incorrect report) or with a preventive action (a measure to prevent a potential nonconformity that has not yet occurred).

Zendo LIMS allows a corrective action to be defined, a responsible person assigned, an implementation deadline set, and effectiveness verification scheduled. The system sends automatic alerts as a deadline approaches, helping ensure that corrective actions are implemented on time.

2.5 Effectiveness verification and closure

A corrective action is not complete until its effectiveness has been verified: it must be demonstrated that the root cause has been eliminated and that the nonconformity has not recurred. Zendo LIMS records this verification with documented evidence and only allows a nonconformity to be closed once this step is complete.

3. Nonconformities in the food & agriculture context

3.1 Alignment with Food Certification Schemes

Laboratories in the food and agriculture sector frequently work with multiple certification schemes: BRCGS (British Retail Consortium Global Standards), IFS (International Featured Standards), and FSSC 22000. All of these schemes share ISO 17025’s approach of continuous improvement based on the PDCA cycle and require documented nonconformity management.

A laboratory that manages its nonconformities in Zendo LIMS — with root cause analysis, corrective action, deadline, and verification fields — simultaneously meets the requirements of ISO 17025 and of food-certification schemes, avoiding duplicate record-keeping.

3.2 Regulatory notification obligations

Under regulatory frameworks such as the EU Drinking Water Directive (2020/2184) and, in the United States, the Safe Drinking Water Act (SDWA), a drinking water test result that exceeds a parametric value generally triggers an obligation to notify the relevant authority without delay — for example, through Spain’s national reporting system (SINAC) in the EU context, or the corresponding state/EPA reporting channel in the US. This means that detecting a nonconforming result is not purely an internal laboratory matter: it has direct regulatory implications that require fast, well-documented management.

4. The strategic value of nonconformity data

When managed systematically, nonconformities generate one of a laboratory’s most valuable data sets. Aggregate analysis of nonconformities reveals patterns that individual incidents do not show.

Patterns by type: If most nonconformities relate to a specific piece of equipment, it may signal the need to replace it or shorten its calibration interval.

Patterns by area: If one area of the laboratory accounts for a disproportionate share of nonconformities, it may indicate training needs or a procedure review.

Patterns over time: A rise in nonconformities during periods of high workload may indicate the need to adjust operational capacity.

Zendo LIMS generates nonconformity trend reports filtered by type, area, equipment, analyst, and period. These reports feed directly into management review, another ISO 17025 requirement.

5. Conclusion: from deviation to competitive advantage

Nonconformity management is far more than an accreditation requirement: it is the mechanism that turns every error into a documented improvement opportunity. A laboratory that manages its nonconformities rigorously — with effective root cause analysis and verified corrective actions — does more than maintain its accreditation: it builds a system that improves with every cycle.

Zendo LIMS digitizes this entire cycle, providing the traceability, deadlines, alerts, and aggregated data a laboratory director needs to demonstrate that their management system is not a document gathering dust: it is a continuous-improvement engine in operation.