Regulatory signs
Weight Limit sign
Vehicles heavier than the number posted may not cross this bridge or use this road.
- Tall rectangle
- White
- MUTCD R12-1
Shape and background first
Federal designation R12-1 in the MUTCD, the national standard every state signs to. Found at the approach to older bridges, timber structures and rural roads with a weak subgrade, sometimes stated as gross vehicle weight and sometimes as weight per axle.
What the MUTCD specifies
Designation: R12-1
MUTCD Section 2B.64
Conventional road size: 24 x 30 in
Standard: Use a weight limit sign where a highway section or structure has a vehicle weight restriction.
Source: Federal Highway Administration, MUTCD 11th Edition (December 2023), Part 2, Table 2B-1; Section 2B.64, verified 2026-09-26.
How states handle it
Some states post the limit in gross tons, others in weight per axle, so the same bridge can look very different depending on which state you are in.
What the test wants you to know
The mistake people make
Weight limit signs are almost always about bridge and pavement structure, not traffic safety, so the number reflects an engineering limit rather than a speed or visibility concern. Ignoring one is a common cause of bridge damage, which is why it often carries a separate, larger fine than a typical moving violation.
