On a limited access highway, during an emergency when your apparatus is not in use, what action is recommended?

• A. Drive through the traffic gap to reach the scene faster
• B. Turn on only the siren for警告
• C. Park behind other vehicles and wait for instructions
• D. Use apparatus as a barrier between the traffic flow and the responders on scene

Answer: (D)

The main idea here is using the apparatus as a protective barrier to shield responders from passing traffic on a limited-access highway when the vehicle isn’t actively in use. Positioning the apparatus in a way that blocks or slows approaching vehicles creates a physical buffer, helping to prevent secondary crashes and giving crews a safer space to work. It also provides clear cues to motorists to slow down and steer away from the work zone, which is crucial on high-speed highways.

Driving through a traffic gap is risky and can cause a collision; turning on only the siren may warn nearby drivers but doesn’t physically protect the scene or control traffic; parking behind other vehicles and waiting for instructions leaves responders exposed without a protective barrier. Using the apparatus as a barrier directly enhances safety for both responders and the traveling public.