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Official United States Low Clearance Overhead Road Sign

Federal MUTCD Specifications

Standard Code
W12-2
Sign Category
Warning
Shape
Diamond
Color Scheme
Yellow with Top & Bottom Arrows & Height Text

Warning Road Sign (W12-2)

Low Clearance Overhead Sign Meaning & Driving Rules

Warns of an overhead bridge, tunnel, or structure with vertical clearance less than 14 feet (e.g., '12FT 6IN').

Required Driver Action & Right-of-Way Protocol

Know your vehicle's exact total height. If your vehicle exceeds the posted clearance, stop and find an alternate route.

Detailed Overview & Purpose

The Low Clearance sign (W12-2) indicates the exact vertical clearance under an overhead structure. Any vehicle taller than the posted height will strike the structure, causing severe damage or bridge collapse.

Commercial trucks, RVs, delivery vans, and vehicles with rooftop cargo must know their exact height before proceeding.

Key Standard & Origin: The clearance posted on the sign is often 3 inches less than the actual measured clearance to provide a safety margin.

Where You'll Find This Sign

Posted on and in advance of low railroad bridges, tunnels, and overpasses with clearance under 14 feet.

Common Driver Mistakes to Avoid

Drivers of rental moving trucks (like U-Hauls) forgetting their vehicle height and driving into low bridges.

How This Sign Appears on the DMV Knowledge & Road Test

Essential question for CDL applicants, RV operators, and rental truck drivers.

Legal Penalties and Moving Violations

Striking an overhead bridge carries massive civil liability, bridge inspection costs ($10,000+), and license revocation.

DMV Knowledge Check

When you encounter the official Low Clearance Overhead (W12-2) on a roadway, what is your legal duty?

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