Why Do Ambulances Drag Chains? (Answered)

One of the things everyone knows is that emergency vehicles such as ambulances tend to receive special treatment on the road due to their nature as first responders in case of any emergencies.

In that case, these vehicles are usually always on the go. But one of the things you may be wondering about ambulances is that they tend to drag chains around as they are moving.

Why do ambulances drag chains?

Ambulances drag chains to make sure that they are always grounded. Making sure that the ambulances are always grounded prevents any static electricity from interfering with the systems in the ambulances. There are also other chains that allow the ambulances the traction they need when driving in snowy conditions.

Ambulance Drag Chains

Some people tend to think that ambulances drag chains to effectively remind the people around them that these vehicles are approaching.

However, there is a special science behind the reason why these vehicles have chains. And you would be surprised to know the reason why these ambulances have chains that they tend to drag around as they move.

Why do ambulances drag chains?

One of the things that everyone knows is that ambulances tend to be different from other vehicles on the road because of the very fact that they are given preferential treatment due to their very nature as service vehicles that respond to emergencies and accidents.

But, as special as these vehicles are, you might be wondering why they are allowed to drag chains around when moving.

There are a lot of instances where people tend to think that ambulances are allowed to drag chains to make enough noise so that the people around them will be reminded of their presence.

In a way, that makes a lot of sense, but you also have to remember that ambulances also have sirens that are already loud enough to alert other people and vehicles within the vicinity.

So, what’s the point of dragging these chains around?

What you should know about air is that it contains a lot of different electrons that constantly make contact with vehicles as they are moving. This is not only true for ambulances but also for any other type of vehicle that is on the move. When a vehicle makes contact with the electrons found in the air as the vehicle is moving, the risk of static electricity increases.

So, when that happens, there will be a chance that the static electricity will end up interfering with the systems inside the ambulance. 

If you must know, ambulances have plenty of different electronic equipment that needs to be in working order, especially if there is an emergency that the responders are attending to.

Ambulances regularly deal with life and death situations. Static electricity that ends up interfering with the equipment may end up making it a lot more difficult for the responders to do their job while the ambulance is still on its way to the hospital.

So, by dragging a chain beneath the vehicle, what happens here is that the ambulance will stay grounded.

That’s because the electrons in the air tend to move from high-density areas to low-density areas. And when the ambulance is dragging a chain, the electrons will now move to the less charged areas on the ground. This effectively protects the entire vehicle from static electricity so that the emergency equipment in the ambulance would be able to function normally.

In some instances, the chains that are dragged around by ambulances are also part of what we call an automatic tire chain system. This system is usually equipped on ambulances not only to make sure that the vehicles are grounded but also to make sure that the ambulances are able to improve their traction when they are driving on slippery roads.

This automatic tire chain system usually involves a number of chains that are attached to the vehicle and are pressed against the tires.

When the tires are rotating, the rotation will cause the disc to spin and allow the chain to swing under the tires. This essentially turns the chains into an anti-skid system that will allow the vehicle to have the traction it needs when driving on slippery roads.

So, for ambulances, this becomes important because these vehicles are always on the move. There will be instances where ambulances may have to drive on slippery roads depending on the emergency they have to respond to.

As such, having an anti-skid system in the form of chains will allow these tires to have the traction they need to move on different types of road conditions without worrying about losing control.

Do other service vehicles have chains hanging?

While we did say that ambulances drag chains for very good reasons, what you should also know is that other types of service vehicles also have chains hanging as well. These include vehicles such as fire trucks and even non-service vehicles that tend to carry gasoline around.

For fire trucks, the main reason why they drag chains around is to allow them to move on slippery roads without worrying about losing control.

Like ambulances, fire trucks are always on the move whenever they need to respond to an emergency situation. Having chains allows them to improve their traction on slippery roads.

On the other hand, large trucks that carry gasoline need to drag chains around because of how dangerous gasoline is when ignited.

Going back to our discussion on static electricity, these trucks always need to be grounded because the electrons in the air might end up igniting the gasoline that these trucks carry around.

Of course, they also need the chains to improve traction because a gasoline truck that ends up losing control may run the risk of igniting the petroleum.

Do school buses have automatic chains?

Another type of vehicle that also has automatic chains is the school bus.

And like service vehicles and large trucks, school buses have these automatic chains mainly for safety purposes because of the very fact that these buses carry children.

This means that the bus driver needs to always be in control over the vehicle.

Having automatic chains will allow the bus to have the traction it needs to drive well on slippery roads, especially during winter and the rainy season.


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