HAZMAT CDL Practice Test

Which signals may be used to warn of a stopped vehicle that contains explosives?

1. Flares

2. Reflective triangles

3. Light signals

4. Emergency lights

The correct answer is: Reflective triangles

Reflective triangles are an essential tool for warning other drivers about a stopped vehicle, especially one that contains explosives. They serve several important functions. First, reflective triangles are designed to be highly visible during both day and night, providing a clear warning that a vehicle is stationary. This is critical for preventing additional accidents or incidents, particularly with hazardous materials that could escalate into dangerous situations. When placed appropriately on the roadway, reflective triangles create a visual cue for approaching drivers, which can help ensure they slow down and navigate safely around the stopped vehicle. This is particularly necessary when the stopped vehicle poses additional risks due to its hazardous contents, like explosives, which are susceptible to ignition or detonation if disturbed. Other options, while they may also provide warnings, are less effective or appropriate for this specific scenario. Flares, while visible, can pose an additional fire risk when used around explosives. Light signals might not have the same immediate recognition and clarity as clearly marked reflective triangles. Emergency lights are useful for attracting attention to a stopped vehicle, but they might not adequately convey the additional hazard that explosives present. Thus, the use of reflective triangles is the most suitable and effective method for alerting others about a stopped vehicle carrying explosives.