How Layers of Protection Reduce Risk

Layers of protection are independent solutions that work together to reduce the risk of a negative outcome. The idea is to put different safeguards in place so that if one fails, another will catch the issue before it turns into a big problem. Even if you’re just now learning the term “layers of protection,” you’ve likely experienced this concept in action—and if you drove to work this morning, you definitely did.

Layers of Protection in Your Car and on the Road

Every time you drive your car, you are at risk of being injured in a car accident. This risk cannot be eliminated unless you remove all cars. However, while the risk of car accident injuries is always above zero, you can take measures to reduce it as much as possible. One measure you can take is to keep your eyes on the road.

One Layer of Protection: Eyes on Road

Keeping your eyes on the road is an important safety measure, but it’s not foolproof. A moment’s distraction can cause this solution to fail. Even if you are focused on the road, you may not be able to react in time to avoid an accident, especially if you’re driving at high speed. Keeping your eyes on the road is a good idea, but this one solution isn’t sufficient to reduce risk to an acceptable level.

Car Rear-Ended Vehicle 3-Why Cause Map™

Let’s add another layer of protection by maintaining a two-second following distance.

Two Layers of Protection: Two-Second Following Distance and Eyes on Road

Combining eyes on road with a two-second following distance creates a stronger defense against accidents. For example, if the vehicle ahead stops suddenly and you’re only watching the road without maintaining a safe distance, you might not have time to react. Similarly, if you maintain a proper following distance but aren’t paying attention, you won’t respond in time either. These two layers of protection work together to reduce the likelihood of being injured in an accident.

Car Rear-Ended Vehicle 5-Why Cause Map™

But are two layers of protection enough? We’ve all heard stories of careful drivers who end up in serious accidents due to factors beyond their control, like a drunk driver or mechanical failure. When lives are on the line, we need more layers of protection.

Eight Layers of Protection

Fortunately, today’s drivers have multiple layers of protection in place to help reduce the risk of car accident injuries. Some solutions, such as brake lights and driving at posted speeds, help prevent drivers from getting into an accident in the first place. Others, like seat belts and airbags, help minimize injury even if the driver gets into an accident. That’s the value of layers of protection: Even if you didn’t keep your eyes on the road, drove too fast, and got into an accident, you might still avoid serious injury thanks to the layers of protection built into your vehicle: seat belts, airbags, and crumple zones.

The eight layers of protection highlighted in our graphic are just a sample of available solutions. Extra-cautious drivers may add even more, and some vehicles offer additional safety features. But this raises the question: Are more layers of protection always better?

Too Many Layers of Protection: Diminishing Returns

Once risk is reduced to an acceptable level, deciding to add more layers involves trade-offs. While additional layers may further reduce risk, the benefits often become marginal or even counterproductive.

For example, wearing a helmet while driving would reduce the risk of head injury in a crash, but most people wouldn’t consider doing so (unless they’re a race car driver). For the everyday driver, seatbelts, crumple zones, airbags, and other built-in safety features provide acceptable protection. Adding a helmet would feel excessive and uncomfortable. It could also reduce visibility and impair hearing, introducing new risks while trying to mitigate others.

Why Settle for One Layer of Protection?

Now that we have covered how effective layers of protection are in reducing risks, the idea of relying on just one layer of protection doesn’t sound like a great idea. But because of “one root cause” thinking, that’s what a lot of people and companies inadvertently do.

A person with this mindset looks at a car accident and says, “The root cause of the accident was that the driver was distracted. To prevent future accidents, drivers should keep their eyes on the road.” In other words: one root cause, one solution, one layer of protection. By ignoring all the other factors that contributed to the accident—speed, following distance, vehicle condition, and so on—you’d miss all the other solution options we’ve discussed here.

Single-cause logic isn’t the way risk is reduced with cars, and it shouldn’t be the way organizations try to reduce risk at work. If you would like to improve the ways you find potential solutions, our Cause Mapping^® Root Cause Analysis workshops are just right for you.