In pharmaceutical manufacturing, the phrase “human error” frequently appears in deviation reports, CAPA investigations, non-conformance records, and regulatory inspection findings. It is often used as the immediate explanation for mistakes such as incorrect documentation, skipped process steps, mislabelling, or procedural deviations.

However, simply concluding that an incident occurred because of human error rarely satisfies modern regulatory expectations. Agencies such as the MHRA, FDA, and EMA increasingly expect manufacturers to investigate beyond the individual and determine why the error occurred in the first place.

In a Good Manufacturing Practice (GMP) environment, where product quality directly affects patient safety, every deviation represents an opportunity to strengthen the quality system. Treating human error as the final answer instead of the starting point can allow the same issues to recur, increase compliance risks, and weaken an organisation’s Quality Management System (QMS).

This article explores what human error really means in GMP, why it is often misunderstood, and how pharmaceutical companies can adopt a more effective, system-based approach to preventing recurring deviations.

Understanding Human Error in a GMP Environment

Human error refers to an unintentional action or decision that leads to a deviation from an established procedure or expected outcome. These actions are not deliberate violations but genuine mistakes that occur during routine operations.

Examples include:

• Forgetting to complete a step in a Standard Operating Procedure (SOP)
• Mislabelling raw materials or finished products
• Incorrect data entry into manufacturing or laboratory records
• Missing signatures or dates in batch documentation
• Using an incorrect material or component
• Performing calculations incorrectly
• Skipping equipment verification before production
• Recording results in the wrong logbook or electronic system

Although these errors are committed by individuals, they rarely happen in isolation. Every action takes place within a system consisting of procedures, training, equipment, workplace design, supervision, and organisational culture.

Therefore, the important question is not “Who made the mistake?” but rather:

“What conditions allowed the mistake to occur?”

Why Simply Stating “Human Error” Is Not an Acceptable Root Cause

Many investigations stop once the operator responsible has been identified. The investigation concludes with:

Root Cause: Human Error

Corrective Action:

• Retrain operator
• Remind staff to follow SOP

While this may appear sufficient, it rarely addresses the actual reason behind the deviation.

Regulatory inspectors frequently challenge investigations that end with “human error” because this explanation:

1. Lacks Depth

It identifies who made the mistake but fails to explain why the mistake happened.

Without understanding contributing factors, similar errors are likely to occur again.

2. Ignores System Weaknesses

Human performance is heavily influenced by:

• Process design
• Equipment usability
• Workplace environment
• Training effectiveness
• Management expectations
• Documentation quality

If these factors are ignored, corrective actions become ineffective.

3. Prevents Continuous Improvement

One of GMP’s key principles is continual improvement.

If every deviation ends with “operator error,” opportunities to improve procedures, automate processes, simplify documentation, or strengthen controls are missed.

4. Does Not Meet Regulatory Expectations

During inspections, regulators expect investigations to demonstrate:

• Scientific thinking
• Evidence-based root cause analysis
• Risk assessment
• Effective CAPA
• Preventive measures

Simply blaming an operator is unlikely to satisfy these expectations.

Human Error Is Often a Symptom of System Failure

Most human errors are consequences of underlying weaknesses within the organisation.

Below are some of the most common contributors.

1. Inadequate Training and Competency

Training is one of the biggest contributors to performance.

Questions investigators should ask include:

• Was the employee fully trained?
• Was competency assessed after training?
• Was refresher training provided?
• Was the employee authorised to perform the activity?
• Were training records current?
• Had the procedure recently changed?

Merely attending training does not guarantee understanding.

Effective GMP organisations assess practical competency rather than relying solely on attendance records.

2. Poorly Written or Complex SOPs

Many pharmaceutical procedures become increasingly complex over time.

Common issues include:

• Excessive document length
• Technical language that is difficult to understand
• Too many cross-references
• Poor formatting
• Missing diagrams or photographs
• Confusing decision points

If experienced employees regularly misunderstand an SOP, the problem may lie with the procedure—not the employee.

Good SOPs should be:

• Clear
• Logical
• Concise
• Visual where appropriate
• Easy to follow under operational conditions

3. Environmental Factors

Even well-trained operators can make mistakes when working under poor conditions.

Examples include:

• High production pressure
• Overtime or fatigue
• Frequent interruptions
• Noise
• Poor lighting
• Excessive heat
• Cluttered workstations
• Inadequate workspace layout

Human performance naturally declines when working under stress.

Investigations should always examine environmental influences.

4. Weak Process Controls

Processes that rely heavily on manual activities naturally have a greater risk of error.

Examples include:

• Manual calculations
• Handwritten labels
• Manual transcription
• Visual inspections without verification
• Single-person critical activities

Risk can often be reduced by introducing:

• Barcode verification
• Electronic Batch Records (EBR)
• Automated calculations
• Independent verification
• Electronic signatures
• Scanning technology

The objective should be to design processes that make incorrect actions difficult or impossible.

5. Poor Equipment or Workplace Design

Human error frequently originates from poorly designed equipment interfaces.

Examples include:

• Similar-looking buttons
• Confusing software screens
• Difficult-to-read displays
• Poor ergonomics
• Inaccessible controls

Human Factors Engineering has become an increasingly important element of pharmaceutical manufacturing because equipment design significantly affects operator performance.

6. Organisational Culture

Company culture strongly influences employee behaviour.

In organisations where mistakes result in blame or punishment, employees may:

• Hide deviations
• Delay reporting incidents
• Modify documentation
• Avoid raising concerns

Conversely, a strong quality culture encourages:

• Transparency
• Early reporting
• Learning from mistakes
• Continuous improvement
• Shared responsibility for quality

An organisation cannot improve what employees are afraid to report.

Conducting Effective Root Cause Investigations

Instead of accepting human error as the final explanation, investigations should identify contributing factors using structured methodologies.

Common tools include:

5 Whys Analysis

Repeatedly asking “Why?” helps investigators move beyond the immediate event to identify the underlying cause.

Example:

Deviation: Incorrect material used.

Why?

Operator selected wrong container.

Why?

Containers looked identical.

Why?

Labels were difficult to distinguish.

Why?

Current labelling system lacks colour differentiation.

Root Cause:

Poor visual identification system not simply operator error.

Fishbone (Ishikawa) Diagram

This method examines contributing factors across categories such as:

• People
• Process
• Equipment
• Materials
• Environment
• Measurement
• Management

It encourages broader thinking rather than focusing solely on individuals.

Failure Mode and Effects Analysis (FMEA)

FMEA proactively identifies where human errors could occur before they happen.

It evaluates:

• Severity
• Probability
• Detectability

This supports risk-based improvements before deviations occur.

Preventing Human Error Through System Design

Rather than relying entirely on operators to avoid mistakes, pharmaceutical companies should design processes that naturally reduce opportunities for error.

Examples include:

Error-Proofing (Poka-Yoke)

Simple engineering controls can prevent incorrect actions.

Examples:

• Connectors that only fit one way
• Barcode verification
• Automated dispensing
• Locked software workflows

Simplified Documentation

Reduce unnecessary complexity by:

• Shortening SOPs
• Using flowcharts
• Including photographs
• Adding checklists
• Using standard layouts

Clear documentation improves compliance.

Visual Management

Visual controls help operators quickly identify correct actions.

Examples include:

• Colour coding
• Shadow boards
• Floor markings
• Status indicators
• Equipment labels

Improved Training Programmes

Effective training should include:

• Classroom instruction
• Practical demonstration
• Competency assessment
• Periodic refreshers
• Observation during routine work

Training effectiveness should be measured not assumed.

Strong Quality Culture

Leadership plays a critical role in reducing human error.

Employees should feel confident reporting mistakes without fear of blame.

Learning organisations improve because they investigate openly and implement meaningful preventive actions.

When Human Error Really Is the Root Cause

There are occasions where an isolated human lapse genuinely represents the primary cause.

Examples may include:

• Temporary distraction
• Fatigue
• Personal stress
• Accidental omission despite adequate controls

Even in these situations, investigations should confirm:

• Appropriate training was completed.
• Procedures were clear.
• Equipment functioned correctly.
• Supervision was adequate.
• Environmental conditions were acceptable.
• The event was genuinely isolated.

Corrective actions may include:

• Targeted retraining
• Additional supervision
• Increased monitoring
• Temporary workload adjustments
• Reinforcement of GMP expectations

Preventive measures should still be considered to minimise recurrence.

Regulatory Expectations

Both the FDA and MHRA expect pharmaceutical manufacturers to demonstrate that investigations identify true root causes rather than assigning blame.

Effective investigations should:

• Be evidence based
• Examine both human and system factors
• Identify contributing causes
• Assess risk to product quality
• Implement effective CAPA
• Verify CAPA effectiveness
• Prevent recurrence

Companies that consistently investigate beyond human error generally demonstrate stronger Quality Management Systems and experience fewer repeat deviations.

Building a Culture That Prevents Human Error

Reducing human error requires commitment across the entire organisation.

Successful pharmaceutical companies focus on:

• Robust Quality Management Systems
• Effective deviation investigations
• Continuous improvement
• Human Factors Engineering
• Ongoing competency development
• Risk-based decision making
• Leadership commitment to quality

When organisations strengthen their systems, employees naturally make fewer mistakes.

Conclusion

Human error should rarely be considered the final answer during a GMP investigation. In most cases, it represents the visible symptom of deeper issues involving processes, procedures, training, workplace design, technology, or organisational culture.

Rather than asking, “Who made the mistake?”, pharmaceutical organisations should ask:

• Why was the mistake possible?
• What system weakness contributed?
• How can the process be improved?
• What preventive controls can eliminate recurrence?

By adopting a system-centred, risk-based approach to investigations, organisations not only satisfy regulatory expectations but also improve product quality, operational efficiency, and ultimately patient safety.

How Q&V Can Help

At Q&V, we support pharmaceutical, biotechnology, and life sciences organisations in building stronger quality systems that minimise human error and enhance regulatory compliance.

Our expertise includes:

• Deviation and non-conformance investigations
• Root Cause Analysis (RCA)
• CAPA development and effectiveness reviews
• Human error reduction strategies
• GMP compliance consulting
• SOP review and optimisation
• Training and competency programmes
• Audit preparation and inspection readiness
• Quality Risk Management (QRM)
• Continuous improvement initiatives

Whether you are preparing for an MHRA or FDA inspection, strengthening your Quality Management System, or looking to reduce recurring deviations, our experienced consultants provide practical, compliant, and sustainable solutions tailored to your organisation’s needs.