Which device should be used to alert nearby workers of danger?

• A. Horn
• B. Alarm
• C. Light
• D. Flag

Answer: (A)

Audible warnings grab attention fastest in a busy crane area. A horn produces a loud, distinctive signal that carries over ambient noise and around equipment, so workers nearby can hear it quickly regardless of their location. This immediacy helps people pause or stop what they’re doing before danger arises. Visual signals like lights or flags depend on someone seeing them and may be blocked by glare, distance, or distractions, and alarms can be confused with other alarms or not tied directly to crane movement. So the horn is the most reliable way to alert nearby workers of danger.