Texas CDL Class B Practice Test (TX) 3

Correct answer: D – Any of these situations

Each listed situation requires evacuation. Mandatory evacuation conditions include an actual or threatened fire, a bus stalled on or adjacent to a railroad-highway crossing, and imminent danger of a collision. Evacuation is also required when the bus's position may change and increase the danger or when a hazardous-material spill creates a need to leave quickly. The driver must direct passengers toward an appropriate safe location.

Source: Texas Commercial Motor Vehicle Drivers Handbook — § 10.3.1, “Planning for Emergencies—Mandatory Evacuations”

Correct answer: A – From 85 to 100 psi

The Texas handbook states that a dual air system should normally build pressure from 85 to 100 psi within 45 seconds when the engine is running at operating rpm. A vehicle with larger-than-minimum air tanks may have a longer acceptable buildup time, based on the manufacturer's specifications. If pressure does not build fast enough, the brakes could lose needed pressure during operation, and the defect must be repaired before driving.

Source: Texas Commercial Motor Vehicle Drivers Handbook — § 5.3, “Inspecting Air Brake Systems—Check Rate of Air Pressure Buildup”

Correct answer: B – When it may help prevent a collision

A horn can warn another road user of your presence and may help prevent a collision. Texas CDL guidance instructs drivers to use it when needed, while recognizing that unnecessary horn use can startle others and create danger. It should not be used merely because another vehicle is inconvenient or moving slowly. The purpose is to give a useful safety warning when circumstances require one.

Source: Texas Commercial Motor Vehicle Drivers Handbook — § 2.5, “Communicating—Use Your Horn When Needed”

Correct answer: D – Any of these conditions

All three are serious brake defects. A cracked drum can compromise the braking assembly, while oil, grease, or brake fluid on a shoe or pad interferes with the friction needed for braking. Shoes that are dangerously thin, broken, or missing cannot perform properly. These conditions should be found during inspection and corrected before the vehicle is placed in service.

Source: Texas Commercial Motor Vehicle Drivers Handbook — § 2.1.2, “Vehicle Inspection Guide—Bad Brake Drums or Shoes”

Correct answer: C – Rail, ship, or both

Containerized loads are commonly used when freight travels part of its journey by rail or ship. A truck typically transports the container at the beginning or end of the trip. Containers with built-in locks may attach directly to a specialized frame; others are loaded on flatbed trailers. Regardless of design, the container must be properly secured, and applicable weight and hazardous-material requirements still apply.

Source: Texas Commercial Motor Vehicle Drivers Handbook — § 3.3.5, “Sealed and Containerized Loads”

Correct answer: A – When the road is wet, icy, or snow-covered

A retarder can cause the drive wheels to skid when they have poor traction. Drivers should turn the retarder off when the roadway is wet, icy, or snow-covered. Retarders help slow a vehicle and reduce brake wear under suitable conditions, but they do not replace proper braking technique. The driver should know how the particular vehicle's retarder is controlled before operating it.

Source: Texas Commercial Motor Vehicle Drivers Handbook — § 2.3.4, “Retarders”