What do the three white lights in a vertical...

Question 1 / 2707066636ee928f7522a1c51a304

Question 1 of 2707066636ee928f7522a1c51a304

What do the three white lights in a vertical line on a multiple-span bridge indicate?

Question 1 of 27070

What do the three white lights in a vertical line on a multiple-span bridge indicate?

🔍 Key Concepts

• Inland bridge lighting signals used to mark safe spans for navigation • Difference between lights marking safe channel spans vs. lights marking hazards/obstructions • How vertical light arrangements on bridges guide vessel operators at night

💭 Think About

• Ask yourself: when approaching a multiple‑span bridge at night, what light pattern helps you find the safest or preferred span to pass under? • Which choice describes information that would be most important for choosing a span before you get close, rather than warning you about something right above you? • Think about how many different signals would be needed: one type to mark the best span, and different ones to mark closed or obstructed areas. Which of the options sounds like a "positive" indication versus a "warning"?

✅ Before You Answer

• Verify which signal is used to indicate the best or main navigational channel on a bridge with many spans. • Check what kind of marking would normally be used if vertical clearance is reduced by scaffolding or construction—would it be a general bridge signal or local safety marking? • Consider whether an "inoperable draw span" would be shown by a standard fixed light pattern on the bridge, or by day shapes, notices to mariners, or other special signals.

Question 1 of 27070

What do the three white lights in a vertical line on a multiple-span bridge indicate?

The river is obstructed under that span

The main channel

Scaffolding under the span is reducing the vertical clearance

The draw span is inoperable

Question 1 / 2707066636ee928f7522a1c51a304

Question 1 of 2707066636ee928f7522a1c51a304

What do the three white lights in a vertical line on a multiple-span bridge indicate?

Back

Question 1 of 27070

What do the three white lights in a vertical line on a multiple-span bridge indicate?