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Accident Causation: Swiss Cheese Model

Updated: Apr 18, 2022

Work place accidents, in this case, accidents within the work zone can be better managed by making known the significance of safe guards in place, no matter how small. The Swiss Cheese Theory (2008) is a popular occupational safety theory in which Professor James Reason explains that a widespread myth is that errors occur "out of the blue" and are highly viable in their form. The truth is errors tend to be predicable and not random.

The theory posits that there are multiple layers of safety in any work zone and that accidents only happen when all of these safety layers fail or "line up" perfectly. These "layers" can be visualized as slices of swiss cheese, constantly moving and rotating. When the holes all line up an accident occurs. By identifying potential safety hazards [holes] and implementing controls to mitigate these hazards, [work zone] accidents can mostly be prevented or injuries reduced/prevented.

Copyright © 2005 Perneger; licensee BioMed Central Ltd.

Reason's Swiss Cheese Theory is widely accepted in the safety field and has been used to explain a variety of minor incidents to major disasters, such as the Space Shuttle Challenger explosion to the Chernobyl nuclear power plant accident. The theory can also be applied to work zone safety.

In a work zone, there are multiple safety hazards that need to be controlled in order to prevent accidents. By identifying these hazards and implementing controls to guard against them, accidents can be prevented or reduced in the cost and damages associated with the occurrence.

The first step in preventing work zone accidents is to identify potential hazards. Common hazards include:

- Poorly designed work zones

- Lack of traffic control devices

- improper signing and pavement markings

- Poorly trained workers

- Worker complacency

- taking short cuts

If multiple safety controls [or slices] are in place, the chances of an accident occurring are greatly reduced. notice the motoring public isn't listed? They are a known risk factor and the reason no of the above examples should ever be accepted on a project. The key is redundancy and not over looking any aspect no matter how insignificant it may seem, you never know when that small short cut we take or pulling a second shift can induce major issues. How often have you or your crew's been a part of:

- "it'll just take us 20 minutes."

- "we can continue as planned, nothing will happen."

- "just run out there, it won't take but a minute."

With statements like this, you're relying on everything else to go perfectly. when does everything ever go perfect for very long? complacency in the work zone is just as dangerous to one's self as it is to the entire crew. enough exposure to enough risk always yields incidents and occurrence of loss.

Accident causation isn't usually caused by unknowns; we know accidents will happen, the significant variable is time - it is our job to prevent or lessen any loss or potential of accidents occurring.

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