DS:7 Understanding Human Error - Causes, Types, and Prevention

 Understanding Human Error: Causes, Types, and Prevention

Human error is commonly defined as "a failure of a planned action to achieve a desired outcome." Errors can arise from various factors at the individual, job, and organizational levels. When these factors are poorly managed, they increase the likelihood of errors occurring in the workplace. In high-risk environments, even minor errors can lead to serious consequences. By understanding human error, organizations can anticipate likely error scenarios and implement strategies to prevent or mitigate their impact.

   

The Nature of Human Error

Errors stem from a range of influences, but the cognitive processes that lead to errors follow consistent patterns. This allows experts to classify human errors into different categories, forming a human error typology. Recognizing the different types of errors is essential for designing effective error prevention and mitigation strategies. To be effective, these strategies must target a broad spectrum of error types.

Errors can occur at two critical stages of a task: planning and execution. A plan can be either adequate or inadequate, and actions (behavior) can be intentional or unintentional.

• When an adequate plan is correctly executed, the desired outcome is achieved.
• If an adequate plan is not followed due to an unintentional action, the desired outcome is not achieved.
• If the plan itself is flawed, even a correctly executed action will not lead to success.

Types of Human Errors

Human error is classified into skill-based errors, mistakes, and violations. Each category reflects different cognitive processes and requires different corrective actions.

Skill-Based Errors

Skill-based errors occur during routine activities when attention is diverted, either by internal thoughts or external distractions. Even highly skilled individuals are susceptible to these errors because repetitive tasks can be performed with little conscious attention.

Skill-based errors are further divided into:

• Slips of Action – Unintentional actions occurring at the execution stage, such as:
• Missing a step in an isolation sequence
• Pressing the wrong button or pulling the wrong lever
• Loosening a valve instead of tightening it
• Transposing numbers when copying information
• Memory Lapses – Forgetting to perform a step, losing track of a sequence, or forgetting an entire plan.

Since skill-based errors are unintentional, retraining or disciplinary actions are ineffective in addressing them. Instead, strategies such as system redesign, checklists, and reminders are more appropriate.

Mistakes

Mistakes occur when an error originates in the planning phase. Unlike skill-based errors, mistakes happen because the plan itself is flawed. People with less experience or incomplete information are more prone to making mistakes. Since these are not intentional, punitive measures are not appropriate.

Mistakes are categorized into:

• Knowledge-Based Mistakes – Resulting from a lack of expertise, leading to trial-and-error decision-making.
• Rule-Based Mistakes – Occurring when rules are incorrectly applied or ignored. These include:
• Incorrect application of a good rule
• Correct application of a bad rule
• Failure to apply a good rule

Some rules that work well in certain situations may not apply universally. Misapplying rules can lead to unintended consequences.

Violations

Violations occur when individuals intentionally deviate from established rules. However, not all violations are errors. A violation is classified as human error only if it fails to achieve the intended outcome. If a violation leads to success without unintended consequences, it may indicate the need to reassess existing rules.

Violations are categorized into:

• Routine Violations – Commonplace behaviors adopted by many employees, such as using restricted stairwells for convenience.
• Situational Violations – Arising due to external factors like time pressure, poor workplace design, or inadequate equipment.
• Exceptional Violations – Occurring in emergency situations where employees believe rules do not apply or will not resolve the issue.

Preventing violations requires understanding the motivations behind behaviors. In many workplaces, productivity is valued over risk management, leading employees to bypass safety procedures. Organizations must balance these priorities to ensure compliance with essential rules.

Addressing Human Error

Effective error management involves a multi-faceted approach:

1. Understanding Error Types – Recognizing whether an error is skill-based, a mistake, or a violation determines the appropriate response.
2. Designing Better Systems – Automating critical tasks, using checklists, and implementing error-proofing mechanisms can reduce skill-based errors.
3. Improving Training – Providing experience-based learning can help reduce mistakes, especially knowledge-based ones.
4. Reassessing Rules – Identifying outdated or impractical rules can prevent unnecessary violations.
5. Encouraging a Safety Culture – Organizations should foster an environment where employees feel responsible for safety without fear of undue punishment.

Conclusion

Human error is an inevitable part of workplace operations, but understanding its causes and classifications allows organizations to develop targeted prevention strategies. By addressing errors at their source—whether through better training, system redesign, or cultural change—businesses can reduce risk and enhance overall safety and efficiency.

Post by 

Department of Occupational Safety & Health Training Institute 

www.doshti.com