As the COVID-19 pandemic rages on, the Swiss Cheese Model of safety is getting some publicity in the context of pandemic defense. The model has been around since the 1990s and has been widely used across industries, from aviation to nuclear power, to help explain layers of defense to reduce risk and improve safety. Using the pandemic example -- coronavirus germs can pass through the holes of the Swiss cheese. But with many layers of cheese -- here, multiple layers of protection from COVID -- we can slow the spread of the disease. A single layer alone (i.e. testing) is imperfect, but with several layers combined (i.e. mask-wearing, social distancing, hand-washing), we can reduce risk of infection. Great metaphor, right?
Now let's apply the Swiss Cheese Model to pedestrian safety. In the winter months of limited daylight, runners and walkers are often opting outside in the dark, which puts them at greater risk of run-ins with drivers. We've all been there -- we're walking the dog at dusk or going for a morning run before the sun is up, and a driver doesn't see us. Too many pedestrians have stories about close calls (or worse) with drivers. Given the risks associated with running in the dark, what are the layers of protection -- our slices of Swiss cheese -- to help reduce risk of collisions and injuries?
It's important to think about risk reduction from a few angles -- what can you do personally, as a walker or runner, to reduce your own risk? What can drivers do to reduce the likelihood of a collision with a pedestrian? And finally, what can city planners do to help improve safety for all road users?
Below are a few examples of layers of Swiss cheese for pedestrian safety at night. When all these layers are combined and occur together, we're all safer on the road during the dark hours.