Driving an emergency vehicle is a major responsibility. The lives of the responders in the vehicle, as well as the driving public are in your hands.
Besides the lives that are at risk, drivers are responsible for one of the biggest physical assets the department owns—the vehicle and all the equipment on board. Emergency vehicle rollovers continue to be an all-too-frequent cause of vehicle damage, serious injuries and fatalities.
Physics plays a big part in most vehicle rollovers including the vehicle dynamics and road conditions. Most roads are crowned, with a higher centerline to allow drainage – and in some rural areas the crowns can be quite exaggerated. Driving on this slope moves the center-of-gravity to the passenger side and it will move even further to the passenger side when you add in the centrifugal force of water moving to that side when rounding a turn to the left.
In these instances, physics will try to push the vehicle off the road while the operator is steering to move the vehicle in the opposite direction. “Physics” could push the vehicle off the roadway, and potentially onto a dropped shoulder, further moving the center of gravity to the passenger side abruptly. The operator, in an attempt to correct the path of the vehicle could pull to the left — causing more weight to shift to the right. At any point of this scenario, the vehicle could roll. This is not the only scenario where physics comes into play. It comes into play anytime the forces acting on the vehicle change including during turns, stopping, accelerating and leaving the roadway.
We need to reduce the negative forces that are acting on the vehicle to keep the center-of-gravity as close to the “level at rest point” as possible. The scientific explanation: the centrifugal force that acts on the load is proportional to the acceleration of the load (force = mass x acceleration). Essentially, the lower the speed, the less acceleration of the load.
But, simply put, the easiest way to prevent rollovers is to SLOW DOWN.
In this article, we are using the term "chief" to represent the organization, since in most departments, the chief is responsible for emergency response.
The chief must take the lead to ensure that vehicles are operated safely and at the very minimum— all motor vehicle laws in your state should be understood and followed. Operators must know the legal rights and obligations they have as the driver of an emergency vehicle and they should receive initial training (classroom and hands-on,) demonstrating knowledge of the guidelines and proficiency handling the vehicle.
The chief should also determine the qualifications, certification, licensing, training and re-qualification needed to operate vehicles — and enforce guidelines that outline the responsibilities for drivers, officers and crews.
For vehicles that are susceptible to rollovers, the chief should assure that training specific to rollover prevention is also provided. VFIS has a Manage Your Risk Bulletin on Vehicle Rollovers - Lessons Learned and a training program covering vehicle rollovers that provide guidance in this area, as well as annual refresher training that is recommended for operators demonstrating proficiency.
The officer is the person in the right seat during the response. They’re responsible for helping assure that the vehicle is operated in accordance with the department’s guidelines and state laws. They also assist the chief to help ensure the safe arrival of the vehicle at the destination.
The officer should handle the nondriving related tasks (like radio and navigation) so the operator can concentrate on driving with minimal distraction. The operator and officer should know where they are going and the most efficient, safest route to arrive at that destination with the least risk — taking into consideration weather, time of day and special circumstances. The officer should never hesitate to have the driver reduce speed whenever the road, weather and/or call conditions dictate this.
The operator has the wheel in his or her hands and has control of the accelerator and brake, so it should go
without saying that they are the first and best line of defense against a rollover. “Too fast for conditions” is cited as a cause or contributing factor in many emergency vehicle collisions —making it essential that drivers not give up control for the sake of more speed.
Want more tips? VFIS has developed a Manage Your Risk Bulletin on Sterile Cabs/Distracted Driving that provides additional information and suggestions.
In emergency services, we’re fond of saying that “seconds save lives”. Some take that to mean we should drive as fast as we can to save seconds. In reality, exceeding the speed limit in a short response area will not significantly reduce the response time, but could have a negative impact on the handling characteristics of the vehicle (stopping distance, centrifugal force during turns, etc.) — greatly increasing the risk of a collision. But in fact, pre-response preparation (being ready to leave when the call comes in) will likely save more time than speeding on the roadway without increasing the risk to your crew and the members of the public.
We continue to see responders getting hurt and worse as a result of avoidable vehicle rollovers – and we’re concerned for the health and safety of all responders. We can help prevent these types of incidents by taking steps at every level to establish a strong organization safety culture. Working together, we can help make sure more of our brothers and sisters make it home.