Safety set in steel

By David Hubbard

Prevost outlines its commitment to safe passenger transport

Prevost, St. Claire, QB, Canada, says its commitment to product safety evolves naturally from its commitment to build structural strength and integrity into its coaches. As such, the company views safety in two equally important dimensions.

Dynamic safety comprises those systems and features that specifically help Prevost operators and drivers avoid accidents.

Passive safety comprises those systems and features that help protect coach passengers in the event of an accident.

The Prevost safety philosophy is set in steel, beginning with the integrated stainless steel chassis. Prevost says its rigorous stress simulations and shakedown testing have proven that the basic framework provides a very strong and durable foundation to house the many other safety components.

Fire suppression
To protect passengers, drivers and the equipment, and prevent a singular incident from becoming more devastating, the Prevost Fire Suppression System features linear and optical infrared detectors that monitor the engine compartment.

The system carries 25 pounds of dry fire suppression chemical released through five nozzles in 10- to 15-second discharges. In the event of an incident, the driver receives both audible and visual warnings.

Tire pressure monitoring
Correct air pressure in all tires is critical to motorcoach safety. Improper inflation is one of the leading contributors to tire failures.

Pressure monitoring guards against heat buildup that only magnifies in an underinflated tire — the leading cause of dangerous blowouts and tread separation.

Prevost says it incorporates a system originally developed for the high-end luxury automotive industry, which samples both air temperature and pressure. The tire-pressure monitoring system warns drivers about sudden or gradual loss of tire pressure, as well as inner-tire failures that are difficult to inspect.

Real-time conditions are integrated into an easy-to-read dashboard display so drivers can see essential tire information within a minute of coach start-up, including spare tire information.

Electronic stability program
The electronic stability program on a Prevost coach compares driver intentions to the actual movement of the vehicle. Prevost says this is the first such system to incorporate rollover and under/over steer protection, which the company says greatly improves stability.

The program selectively applies the brakes on individual wheels based on the driving conditions and vehicle input to help the driver avoid potentially dangerous situations.

Rollover scenario
In a typical rollover scenario a vehicle enters into a curve going too fast on high friction pavement, which causes high lateral forces from the side to affect the vehicle’s center of gravity.

In such a situation, the system removes engine throttle and then applies pressure to all vehicle brakes to quickly reduce vehicle speed, lessening the likelihood of a rollover.

Sliding scenario
In a sliding scenario, the speed of the vehicle going through a curve exceeds the capability of the tires to maintain vehicle orientation, which causes the vehicle to slide and the driver to begin to over steer.

The electronic stability program senses the driver’s intended path with the steering sensor, comparing it to what is actually happening with the yaw sensor. In an attempt to correct the vehicle orientation the program will quickly apply braking pressure only to the appropriate wheels to rectify toward the desired path and reduce overall speed.

Prevost AWARE adaptive cruise braking
This proprietary AWARE adaptive cruise braking is a dynamic safety enhancement to Prevost coaches that provides advance warnings of dangerous situations and automatically intervenes with dynamic inputs to help the driver avoid collisions. Fully integrated with the electronic stability program, the two systems together mitigate situations that could result in loss of control or vehicle rollover.

The forward-scanning radar provides information to assist in maintaining a safe following distance from other vehicles.

Following-distance alert warns the driver if the distance between vehicles is too close and allows the driver time to take action to stretch the potential stopping distance.

When the cruise control is activated and the speed is set, AWARE provides warnings and automatically intervenes with braking and throttle reduction to help maintain the intended following distance.

The stationary object alert activates when the radar detects a stationary object in the coach’s path and allows the driver time to take evasive action.

Vertical exhaust
Vertical installation of the exhaust system reduces heat in the engine compartment, thus allowing for safer maintenance. This configuration also offers greater protection against ground level burns and fires. The company says it reduces peak exhaust temperature by 50 percent.

Xenon vs. Halogen
Prevost coaches come equipped with Xenon, a chemical element which illuminates with greater intensity than Halogen — 3000 lumen as opposed to 1500.

The Xenon lamp is enclosed in a projector lens that allows it to focus all the light intensity in the correct direction — on the road and not in the air; on the right hand side, not toward oncoming traffic.

Three-point seatbelts
Prevost coaches feature three-point seatbelts on a welded rail system that meets FMVSS 210, depending on the specific coach seat make and model.

Swap and Plug Wheelchair Lift
The exclusive Prevost Swap and Plug Wheelchair Lift is strategically placed in the middle of the coach (in front of the drive axle) to maximize accessibility for emergency evacuation. Prevost’s wheelchair lift is unique in the industry because it’s installed furthest away from the most hazardous fire areas, the engine compartment and wheelwells. Sliding doors on the wheelchair lift access helps prevent injury.