Truck drivers tend to drive long hours, causing them to become fatigued, less attentive and more prone to accidents. The Federal Motor Carrier Safety Administration has identified 3 main factors in driver fatigue associated with truck crashes: 1) Disruption of the normal sleep cycle, 2) ongoing sleep deprivation effects, and 3) “time-on-task” fatigue.
- Normal sleep cycle: Generally, darkness triggers the body to release the sleep-inducing hormone melatonin. As a result, most humans are accustomed to a conventional sleep pattern of sleeping seven or eight hours at night, when it is dark. Most artificial light is not powerful enough to keep the body from producing melatonin. Studies show that when someone alters the normal sleep cycle, they are likely to be extremely tired and less attentive early in the morning, and perhaps again in the early afternoon. Many truckers drive in the nighttime hours to avoid traffic on the highways, which can lead them to be less attentive at a time when they do not expect the sleep deprivation to take effect- in the early morning or afternoon.
- Sleep deprivation adds up: Breaking up sleeping periods into small chunks, instead of eight continuous hours of sleep, causes sleep deprivation. Staying awake for 16-17 hours at a time also adds to a “sleep deficit.” Failure to get a good night’s sleep several days in a row creates a cumulative effect. One uninterrupted 8-hour period of sleep now and then cannot erase a trucker’s built-up sleep deficit. It takes more like 2-3 nights of good sleep to sufficiently refresh the exhausted truck driver back to normal.
- “Time-on-task” fatigue: We have all experienced the effects of “time-on-task fatigue,” which is just a scientific way of saying the longer you do a certain task, the less you are able to concentrate on that task. The same phenomenon happens to truck drivers. The longer they are behind the wheel, the less they are able to concentrate on driving, no matter how careful the driver tries to be.
In order to try to reduce the number of trucking accidents caused by driver fatigue, the federal government has enacted Hours of Services Rules. Under the Regulations, over-the-road truck drivers are required to keep detailed logs, recording exactly when and where they have slept, how many hours they have been on-duty, off-duty, driving and resting.
When an accident occurs, the driver’s logs, especially when checked against the “black box” data, can reveal whether the truck driver violated the Hours of Service Rules. For instance, a truck driver is generally not allowed to drive more than 11 hours out of a 14-hour period of duty, after being off 10 hours in a row.
Despite these strict rules, many truck drivers feel the need to ignore the rules, as they are often paid by the trip or by the load delivered. So be careful on the interstate highways, particularly between the hours of midnight and 6:00 a.m., when studies show the highest rate of truck driver fatigue occurs.