Bridge law vs kpra

I hear it all the time here, but no not really. Those two things, while related, are separate.
And you are correct. Bridge law is the weight formula, while KPRA is the length (if any) restriction on how far back the tandems are.

 

I've heard them used interchangeably

 

They should not be, but just like people using safe haven when they mean safe parking, it's not likely to change.

 

California’s requirements have nothing to do with weight, but rather length and turning ability for trailers longer than 48 feet (KPRA)

Other states in the northeast are concerned with “excess tail swing” on narrow streets and tight corners, with 53 foot trailers

And others are in fact concerned about how much weight is confined to a given distance between axle groups (bridge law). They want to spread the weight across a LONGER distance so as to not have so much concentrated in a short span

 

Many names/terms are used interchangeably by the average joe. Doesnt make them right.

 

that use of the bridge law never made sense to me either but its the one that is used the most ...... I kinda hate the red arrows when you need a hole or 2 to scale it legal you are better off keeping the weight legal and violate the bridge law when going over a scale .... better to move it back if you have red arrows when your not going to cross scales because a cop or dot can easily see that

 

I've always heard that a state's Bridge Law is the distance from king pin to center of rear tandem axle. I only recently learned why it's called " Bridge Law". It has to do with the bounce of the trailer doing damage to the joints of a bridge. As I underdtand it, the closer the distance between king pin and tandems..the less bounce it creates..which makes sense to me.

 

Fun trivia: the distance between groups of axles is the "bridge" referred to in the bridge law. So in that sense, KPRA does refer, sort of, to the "bridge" distance.

 

Interesting. Now I'm going to have to do some research...That's how I roll.