Case Study – NAC | National Accreditation Center

Case Study: Detection of Sampling Error and Process Improvement

Background

The laboratory conducts chemical analyses of products received from food manufacturers. In accordance with food safety regulations, every product received by the laboratory must be sampled according to predefined sampling protocols.
During the second quarter of 2025, it was determined in the laboratory’s accreditation assessment that the analysis results of 2 out of 5 different food samples were invalid. These findings brought attention to the existence of non-compliant sampling procedures.

Key Issue Identified in Food Sample Collection Process

Type of Error:

The food sample was collected from an incorrect location and transported in a container that posed a risk of cross-contamination.

Impact and Consequences:

This sampling error led to several critical issues:

Inaccurate test results during food analysis
Customer dissatisfaction due to unreliable outcomes
Increased operational costs caused by the need for retesting
Reputational damage affecting client trust and accreditation credibility

Process Failures Behind the Error:

Non-compliance with sampling protocols by laboratory personnel
Outdated or unreviewed sampling procedures not aligned with current standards
Inadequate staff training, lacking practical and hands-on components

Research Questions

What were the root causes of the sampling error?
Which structural or organizational factors influenced staff behavior?
What impact did the process improvement have on performance and outcomes?

Analysis Process

Data Collection Methods:

Process observations conducted during routine operations
Participant observation involving one week of pre-analysis workflow monitoring inside the laboratory
Semi-structured interviews with 6 key laboratory staff
Review of quality control documents and nonconformity reports

Analytical Approach

A context-based analysis was conducted using a combination of:

Grounded Theory – to identify recurring themes and underlying patterns
Thick Description – to provide in-depth contextual insights into lab practices and behavior

Observations

Category	Findings
Procedure Knowledge	Although 60% of the laboratory staff believed they knew the procedure by heart, significant deviations were observed during actual implementation.
Training Records	The last comprehensive training session was conducted 18 months ago, and three newly hired employees had not received any formal training.
Time Pressure	Due to an increased daily sampling workload, personnel began to rely on shortcuts to meet volume expectations.
Lack of Assessment	The sampling process had not been subject to any internal audits in the past six months.

Corrective Actions Implemented

1-Procedure Update:
The sampling procedure was revised to ensure full compliance with ISO/IEC 17025 requirements.

2-Training Program Redesign:
A new training program was developed, incorporating both theoretical and practical modules to strengthen staff competence.

3-Mandatory Checklist System:
Customized checklists were made mandatory for each sampling activity to standardize execution and documentation.

4-Internal Audit Integration:
The internal audit scope was expanded to include direct physical observation of the sampling process during every audit cycle.

Results After 3 Months

Key Performance Indicators – Before and After Implementation

Indicators	Before Implementation	After Implementation
Nonconforming Sample Rate	7%	0.5%
Customer Complaints	4 (in the last 6 months)	0
Training Participation	45%	100%
Staff Feedback	“Confusing and stressful”	“Clearer and safer”

Emphasis on Meta-Skills (Based on Nitin Nohria’s Framework)

Meta-Skill	Observed Improvements
Preparation	Staff demonstrated greater mastery of procedures following the enhanced training program.
Discernment	Critical control points in the sampling process are now better identified and prioritized.
Bias Recognition	The assumption of “I already know this” was effectively challenged through structured training.
Judgment	Staff are now better able to assess when sampling should not be conducted.
Collaboration	Sampling and analysis teams operate with improved synchronization and communication.
Curiosity	Personnel began asking more questions about ISO standards and best practices.
Self-Confidence	Post-training, staff carry out their tasks with noticeably greater confidence and clarity.

Lessons Learned

1-Knowing a procedure does not guarantee correct implementation.

2-Lack of audits leads to procedures remaining only on paper.

3-Corrective actions should target not only documentation but also behavior.

Theoretical Insight

This case serves as a typical example of the relationship between social structures (e.g., organizational pressures, time constraints) and individual behavior (e.g., procedural compliance).
In this context, C. Wright Mills’ distinction between “personal troubles” and “public issues” is particularly relevant: what appears to be an individual error by laboratory personnel is, in fact, the result of a systemic organizational failure.

General Applicability

For other laboratories:
The mere existence of procedures is not enough; they must be practically applicable and sustainably integrated into daily workflows.
For training systems:
Training frequency and content must be regularly reviewed and updated to reflect current practices and standards.
For audit mechanisms:
On-site process audits are more effective than paper-based compliance checks in identifying real issues.

SWOT Analysis – Sampling Process in a Food Testing Laboratory

Strengths	Weaknesses
• Accredited laboratory (ISO/IEC 17025 certified)		• Incomplete implementation of sampling procedures in the field
• Qualified and experienced technical personnel		• Lack of regular and periodic staff training
• Established Quality Management System (QMS)		• Tendency of staff to take shortcuts under time pressure
• Rapid response to identified issues		• Delays or absence of internal audits
• Measurable impact of corrective actions within short timeframes		• Procedures known theoretically but neglected during practical application

Opportunities	Threats
• Transition to digital sample tracking systems	• Repeated nonconformities in accreditation audits may jeopardize certification
• Benchmarking and knowledge exchange with other laboratories	• Loss of operational knowledge due to staff turnover
• Collaborations with universities to update training modules	• Clients increasingly selecting labs based on service quality
• Automation of sampling workflows to reduce human error	• Growing demand for analyses may exceed current personnel capacity

SWOT-Based Strategic Recommendations

Area	Strategy
Strength + Opportunity (S-O)	Qualified personnel and the existing Quality Management System (QMS) infrastructure can be utilized to establish efficient digital sampling processes.
Weakness + Opportunity (W-O)	Training gaps can be overcome through well-designed modular training systems.
Strength + Threat (S-T)	Existing quality management systems can proactively prevent potential accreditation risks and threats.
Weakness + Threat (W-T)	Internal audit deficiencies and knowledge loss can be minimized through an effective document management system.