Driving Safety

Driving Safety An Emphasis on the ATV Interagency Driving Policy Guidance has been adopted by the National Wildfire Coordinating Group (NWCG). The NWCG will be issuing a revised policy on Driving Safety in the near future. The revised 2004 policy will be posted on this web page as soon as it is issued. Lessons Learned: Driving and Wildland Fire (article from the WFLLC) Side Mirror Adjustments Driving safety videos available from the Missoula Technology and Development Center: "Focus on the Mission," "Backing Up on Forest Roads," and "Driving on Mountain Roads." Go to Reference Materials for more information.

Common Denominators of Serious Wildland
Fire Related Vehicle Accidents

By Mark T. Bailey, ACTAR No: 1075

When the causes of the 2002 and 2003 serious wildland fire vehicle accidents were examined, six major common denominators involving human factors and three major common denominators involving vehicle characteristics that differ from regular automobiles were identified:

Introduction

A review of the 2002 and 2003 wildland fire serious accident driving reports has yielded some very common accident denominators. The most prevalent cause of injury or death is due to the overturning (rollover) of the vehicles that are being utilized to transport the firefighters and/or water to the fire site. Several of these rollovers led to occupant ejection due to seat belts not being worn. In each and every case, the overturning vehicle was not the cause of the accident, but was the most severe event in a series of events leading to injury or death. The principal causes in the vast majority of these serious accidents were human factors, namely perceptual errors.

Perceptual Errors

Driving is basically a "perceptual-motor oriented task" requiring the driver to process information from the roadway and vehicle, and to act accordingly to maintain safe control of the vehicle. Perceptual errors that resulted in the majority of these serious accidents were caused by inattention, alcohol use, fatigue and inexperience. The most prevalent of these perceptual errors that led to rollovers was inattention or inexperience by failing to perceive a safe speed for curves or turns in the roadway.

Most firefighter vehicles, especially tenders and engines, operate and handle much differently than regular automobiles. This is due to their high center of gravity, weight, suspension, braking system and "surge" (surge is the shifting of water in the water storage tank). Due to these vehicle characteristics, "excess speed" could actually be below the posted speed limit signs. It is not uncommon for engines or tenders to overturn at speeds below the recommended posted speed for a curve. Additionally, failure to slow down well before negotiating a curve can be just as critical in leading to a rollover as misjudging the safe speed of the curve. This is often due to the operator of this type of vehicle not understanding that the slowing and stopping characteristics are not nearly as efficient as that of a passenger car. Many people wait too long to apply the brakes and begin to slow down or come to a complete stop.

A large truck, such as a tender or engine, when equipped with properly working air brakes, only achieves a maximum of eighty-five percent braking efficiency when compared to a passenger car. Additionally, air brakes typically have about half a second of "lag time" which is the time it takes the brakes to actually engage after pressing down on the brake pedal. Eighty-five percent of braking efficiency and a half second of time might not seem substantial, but collectively it is significant.

Example:
A passenger vehicle travelling at 45 miles per hour (66 feet per second) on an average asphalt roadway would come to a stop in about 97 feet in 2.92 seconds during hard braking. An air brake equipped truck travelling at 45 miles per hour on the same road surface would come to a stop in 147 feet in 3.44 seconds.

In the real world it would take the truck even longer to stop since these figures assume cool and perfectly adjusted and performing brakes on the truck (a rarity for air brakes) and didn't account for "surge" from the water tank. Even converted engines with regular hydraulic brakes such as a pickup truck, can still take longer to slow due to excess weight and "surge." Regardless of which braking system a vehicle has, the later and harder the brakes are applied, the more "surge" can have an adverse reaction to the vehicle stopping distance. That is why a professional tender or engine driver will slow down smoothly well before a curve or turn has to be negotiated.

Alcohol & Driving

There were two accidents involving alcohol during this review period, resulting in multiple fatalities. Alcohol is the single largest human condition factor that adversely affects driving performance leading to fatal accidents. Alcohol acts on the central nervous system such as the cells of the cerebral cortex, the body's command center. This slows the motor response of the brain, greatly decreasing perception, information processing and reflexes. Risk taking however, is increased. Alcohol also impairs vision by acting on the optic nerve in the process of sending images to the brain. This can lead to unsafe overtaking due to false distance estimates, slower recovery time from glare, increased duration of eye fixations, reduced peripheral vision and tunnel vision. Studies have shown that even low alcohol levels (significantly lower than State Driving Under the Influence (DUI) levels) cause significantly reduced information processing in the brain and deteriorating driving skills. Alcohol of any amount is too much to safely operate a motor vehicle.

Fatigue

The last of the identified human factors, fatigue, was a contributing factor in six of the serious accidents in this review, three of which resulted in a rollover. In the trucking industry, fatigue is now garnering more interest than ever. A study of 225-truck accident reports by the AAA Foundation for Traffic Safety, indicated that fatigue was a probable or primary cause in 41% of the accidents. Firefighter fatigue can be attributed to working, long, hard, irregular hours, with inadequate sleep. Fatigue when driving can lead to poor judgement, inattention, vehicle wandering and falling asleep at the wheel. Even with adequate rest breaks, firefighter schedules often contradict with our "natural circadian rhythm clock" schedules of being awake during the day and sleeping at night, thus further contributing to fatigue. Due to the aforementioned types of vehicles driven by firefighters, fatigue can take a dangerous situation such as drifting off of the road, and turn it deadly with a subsequent rollover.

This is especially true for 15 passenger vans that are often used to transport firefighters. When these vans are fully loaded with occupants, they become top heavy and the propensity to roll increases. A natural tendency for a driver whose vehicle has drifted off of the roadway and the wheels have dropped off the pavement is to steer hard back onto the road. While this practice is often forgivable in a normal passenger car, it is likely to cause a rollover in a top heavy or high center of gravity vehicle. If a vehicle, or one of its wheels does drift off of the roadway, the operator should slow gradually, and then ease back onto the road when it is safe to do so.

It is important for all vehicle operators to recognize signs of fatigue. These can include yawning, vision difficulties or sore eyes, making fewer and larger steering corrections, restlessness, having trouble maintaining a steady speed, having difficulty staying in the lane, struggling to keep your eyes open, and a heavy headed feeling (nodding).

There are several widely published reports and even "alert devices" on how to combat driver fatigue, none of which are as effective as simply getting adequate sleep and taking scheduled breaks. If you do feel fatigued behind the wheel, pull over in a safe location, take a break, stretch your legs and get some fresh air.

Lack of Seat Belt Use

Many of the fatalities in this review could have been avoided had seat belts been used. All vehicles, regardless of age, should be equipped with seat belts. All fire agencies have mandatory seat belt policies. The issue is voluntary compliance. People need to be aware of recent statistics that show while only twenty-five percent of people still do not wear seat belts, this one person in four minority accounts for a whopping sixty percent of all vehicle deaths. A study by the NHTSA in 2001 identified a seventy-five percent death rate of occupant ejections involving passenger car fatalities. Only one percent of those occupants had been wearing seat belts. During the past 26 years, seat belts have prevented over 135,000 fatalities. It has been estimated that during this same period, if all vehicle occupants had been wearing seat belts, a further 315,000 deaths and 5.2 million injuries could have been prevented.

Conclusion

The keys to avoiding the pitfalls of these human factor accidents are driver education, hands on training and refresher training. Vehicle operators should receive supervised driver education in a controlled environment and become completely familiar with each vehicle's characteristics. Hands on training should include completing a pre-trip vehicle safety inspection and knowledge of the vehicles load capacity. The training should conclude with a road test to demonstrate the operator proficiency of each vehicle to be driven. Refresher training should also be provided since another human factor, redundancy, often leads to complacency.

Mark T. Bailey is a Certified and Accredited Traffic Accident Reconstructionist. He operates his own Collision Consulting practice and has among his credentials over 20 years experience with one of the largest U.S. Government fleet operators.

Mr. Bailey can be reached by telephone at (888) he-hit-me (434-4863) or by e-mail at hehitme@frazmtn.com.