Why Do Trains Use Buffer Cars? | Explained

What are Buffer Cars? Why Do Trains Need Buffer Cars?

We recently dove into why DruBit trains don't need a buffer car, but we did not explain why buffer cars are needed in the first place. Or even what a buffer car is.

That's the point of this video.

A buffer car is a railroad car placed between a train's locomotives and cars containing hazardous materials, particularly unit trains carrying oil or ethanol.

The theory behind using the cars is that they act as a physical barrier, preventing the locomotive from directly impacting hazardous materials in a derailment. They are intended to create separation and absorb an impact.

The idea is to reduce, not eliminate, the risk of explosions, fires, and other dangerous incidents in the event of an incident.

Buffer cars are typically filled with non-hazardous materials like sand, rock, or pebbles. I have even seen tank cars filled with corn syrup on an ethanol train.

The ultimate decider on buffer cars is regulation. Railroads legally have to use a buffer car when a train is made up of hazardous materials.

Buffer cars must be a boxcar, covered hopper, gondola, or tank car. The buffer cannot be a flat car.

They must have a high-strength coupler and be at least 45 feet, but not greater than 75 feet.

The cars must be loaded with a non-hazardous inert material that does not shift in train service.

It is the responsibility of the shipper to provide buffer cars that are in good mechanical condition.

Sources used:
UP.com
Trains.com
FreightWaves.com
Transportation.gov