Safety Tidbit 7.02 - Swiss Cheese Paradigm

Safety Tidbit 7.02 – Swiss Cheese Paradigm

Reference: Reason, J. (2000). Human error: Models and management. BMJ : British Medical Journal, 320(7237), 768. https://doi.org/10.1136/bmj.320.7237.768

This Safety Tidbit was written by my student, Ms. Sarah Messick – a senior in the Safety Sciences Program at the Indiana University of PA graduating Spring 2022.

James Reason proposed the "Swiss Cheese Model" to explain the occurrence of system failures, which looks at preventing hazards from causing human losses by creating barriers. The cheese slices are "barriers," or items set in place by management to help defend against the hazard, such as guards, policies, procedures, rules, and processes.  The "holes" in the cheese are system failures. Some holes or failures are operational, while others are latent conditions. Employees' operational failures are errors, such as slips, lapses, mistakes, or rule violations. Latent conditions are ongoing conditions within an organization allowing errors to occur or failure to correct errors. A couple of examples include poor maintenance or the lack of a process correctly prioritizing issues. The model itself shows that the cheese slices are layers of defense that lie between hazards and accidents. Furthermore, the model reflects flaws in each layer (holes), and when properly lined up, an accident can occur.

The defenses are the barriers intended to protect against errors or hazards, mitigate the consequences of a hazard, or promote a consistent action. An example of a sequence of events within this model would be an engineered issue such as a lack of safeguards, along with an administrative issue, an individual or a worker not using the guard properly would then lead to an incident.

Hope this was helpful and thank you for reading my Safety Tidbits! Comments and questions are always welcome. ~ Bryan

 

P.S. If you have a new safety or health question, please let me know.