Formula Law
CMVs are required to pass through weigh stations at the borders of most states and some large cities. These weigh stations are run by state DOTs, and CMV weight and size enforcement is overseen by the FHWA. Weigh stations check each vehicle's gross weight and axle weight using a set of in-ground truck scales, and are usually where a truck's compliance with the formula is checked.
FMCSA regulation §658.17 states:
- No vehicle or combination of vehicles shall be moved or operated on any interstate highway when the gross weight on two or more consecutive axles exceeds the limitations prescribed by the following formula:
- w = the maximum weight in pounds that can be carried on a group of two or more axles to the nearest 500 pounds (230 kg).
- ℓ = spacing in feet between the outer axles of any two or more consecutive axles.
- n = number of axles being considered.
Two or more consecutive axles may not exceed the weight computed by the bridge formula, even if the gross weight of the truck (or the weight on one axle) is below otherwise legal limits. Although this means that any two axles must comply with the formula, experience has shown that axles 1 through 3, 1 through 5, and 2 through 5 are critical and must be checked. This means that the axle group which comprises the entire truck (known as the "outer group") and the interior axle groups (known as the "tractor group" and "trailer group") must also comply with the bridge formula. If these combinations are found to be satisfactory, then all of the other axle groups on this type of vehicle will usually be satisfactory.
Penalties for violating weight limits vary between states (bridge formula weight violations are treated as gross weight violations), as the states are responsible for enforcement and collection of fines. Some states, such as Connecticut, issue fines on a percentage basis (e.g. 20% overweight at $10 per 100 pounds / 45 kilograms), which means larger trucks pay higher fines. For example, a truck with a legal gross limit of 20,000 pounds (9,100 kg) that violates the limit by 5,000 pounds (2,300 kg) would pay a fine of $500, while a truck with a legal gross limit of 60,000 pounds (27,000 kg) that violates the limit by 5,000 pounds would pay a fine of $250. Other states, such as New York, issue fines on a per-pound basis (e.g., 5,000 pounds overweight equals a $300 fine). Others, such as Massachusetts, impose a less complicated fine schedule whereby a vehicle that violates the limits by less than 10,000 pounds (4,500 kg) is fined $40 per 1000 pounds, while a violation over 10,000 pounds pays $80 per 1000 pounds (e.g. 5,000 pounds overweight equals a $200 fine).
Some states require overweight trucks to offload enough cargo to comply with the limits. In Florida, any vehicle that exceeds the limits by more than 6,000 pounds (2,700 kg) is required to be unloaded until the vehicle is in compliance. Florida also includes a scale tolerance, which allows for violations of less than 10% to be forgiven, and no fine issued. Florida also allows for a load to be shifted (e.g., moved from the front towards the rear of the vehicle) for the vehicle to comply with axle weight limits, without penalty.
Read more about this topic: Federal Bridge Gross Weight Formula
Famous quotes containing the words formula and/or law:
“Given for one instant an intelligence which could comprehend all the forces by which nature is animated and the respective positions of the beings which compose it, if moreover this intelligence were vast enough to submit these data to analysis, it would embrace in the same formula both the movements of the largest bodies in the universe and those of the lightest atom; to it nothing would be uncertain, and the future as the past would be present to its eyes.”
—Pierre Simon De Laplace (1749–1827)
“Unless we maintain correctional institutions of such character that they create respect for law and government instead of breeding resentment and a desire for revenge, we are meeting lawlessness with stupidity and making a travesty of justice.”
—Mary B. Harris (1874–1957)