While OSHA’s Hierarchy of Hazard Controls is well known and universally accepted, the concept of Human Performance (controls that increase awareness) is less understood and not currently utilized effectively.
OSHA has been moving towards the use of Human Performance (HP) modeling for Risk Reduction for the last few years. Now NFPA 70e 2018 has moved HP from its Informative Annex to the front cover of the 2018 standard. This move boldly signals the introduction of HP into the main-stream of Hazard Risk Reduction.
The basic principles of Human Performance are:
- People make mistakes.
- Error-likely situations and conditions are predictable, manageable and preventable.
- Individual’s performance is influenced by organizational values and processes.
- People achieve high levels of performance largely because of encouragement and reinforcement received from leaders, peers and subordinates.
- Incidents can be avoided through an understanding of the reason mistakes occur and application of the lessons learned from past incidents.
According to Rasmussen Performance Model used to classify human error, workers operate in one or more of the three modes:
- Rule-based
- Skill-based
- Knowledge-based
We as humans have limited attention spans. Some work requires more attention to perform than others. The level of attention required of any one task is defined by the worker’s familiarity with the work being performed. Increases of skill, knowledge and experience with the work decreases the level of attention given to the work. Critical points in activities, when risk is higher, require an increase in attention. Focusing attention at these critical points can be improved by training, development/implementation of Standard Operating Procedures (SOPs), equipment design, and teamwork.
Taking a closer look at Rasmussen’s Performance Models of how a worker interacts when performing task…
Rule-based Human Performance Mode is the most desirable of the three models. Typically, the work is something they have been trained for, or is covered by an SOP. It’s called rule-based as the rules were learned by formal or on-the-job training.
Knowledge-based Human Performance Mode is when there are no rules or SOPs available. The worker must rely on their understanding and knowledge of the situation, related principles, and fundamental theory to develop a solution. The tendency to use only the information at hand leads to faulty decision-making and, as such, introduces or overlooks hazards.
Skill-based Human Performance Mode is where worker’s performance is guided by the mental instructions developed by either practice or experience and is less dependent on external conditions. A familiar workplace procedure is typically performed in a skill-based mode, such as the operation of a low-voltage molded case breaker.
Error Precursors are situations when the demands of the work and the environment it is performed in exceed the capabilities of the individual(s) or the limitations of human nature. Consistent use of HP tools by an organization will facilitate the incorporation of best practices work. When error precursors are identified and addressed, the likelihood of human error is reduced. for a better understanding of these tools, see Table Q5 in Annex Q of NFPA70e 2018. While creating your Job Planning and Pre-Job Briefing tools, the use of Table Q5 allows for a graded approach when identifying error precursors. Once identified, we can then select an appropriate HP tool or combination of tools to eleminate or reduce the hazard.
In closing, it’s vitally important that an organization’s procedures, SOPs and values recognize that people make mistakes. The policies and goals of an organization influence worker’s and supervisor’s performance. The reduction or elimination of hazards requires that all members at the workplace cultivate and consistently support the use of HP tools and principles. Establishing a blame-free culture that supports incident reporting and proactively identifies and reacts appropriately makes for a safer, happier work environment.
John Henle
29 CFR 1926 OSHA Outreach Trainer
Bailey Safety
502-639-0248