What action must Echo 6 take upon initiation of a klaxon?

• A. Stop vehicle traffic from entering MPA
• B. Acknowledge with radio
• C. Evacuate to assembly area
• D. Lock all doors in the facility

Answer: (A)

When the klaxon sounds, the immediate priority is to secure the area by stopping vehicle traffic from entering the MPA. Limiting movement at the access point prevents unauthorized entry, reduces the chance of interfering with responders, and helps preserve the scene for safety actions and investigation. Coordinating via radio is important for situational awareness, but it doesn't replace the need to physically control entry right away. Evacuation or lockdown are actions that depend on explicit directions or a specific scenario; they aren’t automatic responses to a klaxon. The key idea is to quickly blockade entry to keep the area secure and under control until further instructions are given.