Why do ambulances have those chains hangging down under them?

Question

I always notice that most ambulances have chains hanging down. Whats the reason or use of these chains?

Answer 1

Because they carry pure oxygen (which is highly flamable) they chains help prevent any static discharge.

Answer 2

Nope, and Nope.

Those chains (I assume your ambulance is in a place where it snows) are called "OnSpots."

Theyre automatic tire chains that stay retracted until the driver hits a switch on the dash that activates an air compressor that makes the lever holding the chainwheel drop down and contact the inside tire which starts the chains getting constantly thrown under the wheel, providing traction while movig forward or backwards and for braking in slippery conditions.  Once the vehicle is on dry roads again, the driver turns them off and they retract back up by the rear axle until needed again.  I have those on the bus I drive.

They are noisy, but after a few miles of listening to the jingling, I don't really hear 'm anymore.

Answer 3

Discharge static electricity which can be dangerous around oxygen tanks

Answer 4

Check out this site and it will explain everything to you.

http://www.onspot.com/indhisfr.htm