Which barrier is a stationary system to prevent falls from a bridge?

• A. Guard rail
• B. Unseating prevention device
• C. Bridge collapse prevention device
• D. Expansion joint

Answer: (A)

The barrier that prevents falls from a bridge is the guard rail. A guard rail is a fixed, permanent barrier installed along the edge of the bridge deck, designed to keep people and vehicles from leaving the roadway and falling over the edge. It is attached to the structure and remains in place under typical use and accident loads, making it the stationary protective element intended for fall restraint.

The other options don’t serve this purpose: an expansion joint is a gap that accommodates deck movement due to temperature changes; an unseating prevention device and a bridge collapse prevention device refer to systems aimed at maintaining structural seating or overall stability, not acting as a continuous edge barrier to prevent falls.