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Comment by calvinmorrison | Hacker News Reader

I was under the impression that we had DOT bumper regulations that the bottom of the bumper couldn't exceed 24 inches. I was brought to this attention when a school bus decided to backup and went over my entire hood causing no damage. It's bumper was roughly at eye level for me!

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In brazil the government requires tall vehicles to have two bumpers, the normal OEM one, and an extra one intended to stop smaller vehicles crashing into the back of the tall one.

This was because eye-level bumpers tend to decapitate people during pile-ups... since they are, after all, eye level...

It would be nice if the US adopted a law like that... I guess that requires too much governmental competence.

For commercial trucks, there is a law - search “Mansfield bar” or (possibly NSFW image) https://sparebumper.com/the-mansfield-bar-jayne-mansfield-an...

It seems crazy that it doesn't apply to civilian vehicles too

It does but it only gets enforced for new vehicles. See the rear bumper mods that were required for the Mercedes G-Wagen 4x4 Squared. Note that federal regs prevented the activation of the LED aux lights for these as well.

https://youtu.be/kgcAA4HUxuE?t=229 https://youtu.be/kgcAA4HUxuE?t=388

The problem is that most of the inappropriately-tall consumer vehicles get that way after the fact. I.e., people modify them. If this is only getting enforced at the manufacturer level, instead of the vehicle-inspection level, it's not going to accomplish much in that category.

Passenger vehicles don't need a Mansfield bar, because their primary crash structure has to be between 16 and 20 inches from the ground.

We have those here too. They aren't very effective. https://www.snopes.com/tachyon/images/photos/accident/graphi...

The standard could be improved, and they don't prevent everything, but in general they are effective.

https://www.iihs.org/news/detail/iihs-recognizes-semitrailer...

Note that this does not address the fact that high bumpers are death for pedestrians. This addresses the issue of collisions with cars, but tall vehicles in general are really bad for pedestrians.

> high bumpers are death for pedestrians

The typical counter-argument to that involves some sort of abuse of the notion of freedom.

(Not endorsing, of course, just mentioning it.)

"People are stupid" is not a valid argument to move towards a solution. "Developing and establishing Standards, training appropriate authorities and giving them the right tools/equipment to measure/identify violators, legislate appropriate fines" is. Hand anyone who does this a $1000 fine, and see how fast the whole country falls in line.

There is the adage about freedom ending at the point my fist meets your face. In this case, I guess it's more about where my face meets your windshield.

A tall profile is pretty much inevitable for vehicles that carry cargo. Even places with strict pedestrian safety standards haven't solved that.

The problem is that we have way more tall profile vehicles out there than we do cargo being carried. It's not really a necessity, lots of people are just buying these things because they like the aesthetic moreso than having any practical need for them.

Plus I'm not even sure the general statement is really that true. The El Camino was a regular car profile. If you're just buying a pick up to haul furniture around rather than, say, bales of hay you don't need it to be that tall.

I was referring to commercial trucks, in line with the above commenters mention of Brazillian truck underride guards, which also are required in the US. Commercial trucks all around the world have a high profile.

The only thing in the US that is different is that passenger vehicles don't have as strict of pedestrian standards as the EU.

I'm just saying: a semi and a lorry have the same pedestrian-unfriendly profile.

> A tall profile is pretty much inevitable for vehicles that carry cargo.

But a tall profile does not mean that headlights need to be mounted higher above the road surface. This is a simple problem in geometry.

> inevitable for vehicles that carry cargo

But not for a vehicle that carries one person

In the US trucks are required to have 'Mansfield Bars' after Jame Mansfield who died in an accident with a trailer truck.

https://www.mentalfloss.com/article/28155/how-jayne-mansfiel...

Lights can become higher at the same bumper height when grilles become taller, as is happening with a lot of pickups and SUVs.

There are definitely regulations for the range of heights headlights must be placed within. It's a fairly large range though.

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