Introduction to the Trucking Industry
Adapted from Truck Driver Occupational Safety and Health 2003 Conference Report and Selective Literature Review (Revised 2007)
by Gregory M. Saltzman and Michael H. Belzer
The U.S. trucking industry is essentially divided into three main segments: government entities, private carriers, and for-hire motor carriers. Government entities such as the U.S. Postal Service operate truck fleets for their own use. Private carriers (wholesale, service, or industrial companies) may sell transportation services to others, although they primarily haul their own freight. For-hire motor carriers receive all of their freight from shippers. The for-hire trucking industry is commonly grouped either by shipment size (parcel, less-than-truckload [LTL], and truckload [TL]), or by geographic scope (local, regional, inter-regional, national, or international) and type of commodity or operation.
The structure of the U.S. trucking industry changed radically soon after deregulation in 1980. Formerly regulated common carriers that had assumed health care and pension costs found it difficult to compete with new non-union TL carriers that had no pension or health care liabilities and little capital overhead. Trucking has shifted from being predominantly unionized before deregulation in 1980 to less than 15% unionized today. Driver wages (adjusted for inflation) have fallen 30% since 1980.
The Federal Motor Carrier Safety Administration issued the latest hours-of-service rules for commercial truck drivers in 2005.1 The new rules increase the minimum daily off- duty time, yet allow drivers to spend more total time working and more time behind the wheel than the previous regulations. For solo drivers, the mandatory break period after a shift has increased from 8 to 10 hours, offering greater opportunity for a driver to obtain restorative sleep, and all work must be completed within 14 hours of the driver’s start time, making it more difficult to falsify log books. However, the new rules also increase the maximum allowable daily driving time from 10 hours to 11 hours, and they allow drivers to work as much as 84 hours in a seven-day period. Drivers were previously limited to 70 hours of work time within any seven-day interval, but a new “restart” provision allocates a fresh set of work hours to a driver after 34 hours of continuous off- duty time (theoretically, two sleep periods). Thus, a driver can now complete 70 hours of duty time early in the 5th day of the week, take 34 hours off, and work another 14 hours in day 7, for a total of 84 hours.
​
U.S. drivers are allowed to work more hours than their counterparts do in either the European Union or Australia’s eastern states. While the daily work schedule allowed in Australia’s eastern states (14 hours of work and 12 hours driving in a 24-hour period) is similar to the U.S. hours of service rules, the Australian drivers are limited to 72 hours of working time in a seven-day period, 12 hours less than the U.S. “restart” provision allows. Drivers in the European Union (EU) are allowed even fewer hours; the latest EU rules will eventually limit all truck drivers to an average of 48 hours per week (over a four-month period), and a maximum of 60 hours per week. Currently, all EU drivers are limited to 9 hours of driving per day.
​
Long working hours, irregular shift and day-off patterns, and many consecutive nights away from home and family can make truck driving an arduous career. The overtime pay provisions of the Fair Labor Standards Act, which require time-and-one-half pay for work hours in excess of 40 per week, do not apply to truck drivers. Drivers are often paid by the mile, and they are not compensated for the time they spend waiting at the docks or performing tasks such as loading and unloading, which make up approximately 25% of their total work time. The American Trucking Associations cite the combination of undesirable working conditions and low wages as reasons for the 121% driver turnover rate in the large truckload sector for 2005.
​
Chemical and ergonomic hazards
Truck drivers face a variety of chemical exposures. Drivers who deliver unhardened concrete are exposed to chromium and alkaline substances, putting them at risk for both allergic skin reactions and chemical burns. Drivers of gasoline tanker trucks often experience acute headaches, dizziness, or nausea after exposure to vapors released during gasoline transfers. Diesel exhaust has been linked to lung cancer and allergic inflammation, and exposure can be substantial at loading docks and truck stops. Increasing the allowable working hours for drivers increases the risk that their exposures to hazardous substances will exceed recommended limits.
​
Ergonomic risks vary widely and can include loading and unloading heavy cargo (beverage delivery drivers handle approximately 36,000 pounds each day), awkward postures, and working in tight spaces such as the drum of a ready-mix concrete truck. The effects of these hazards are borne out by the high number of injuries reported by drivers both in the U.S. and abroad.
​
Fatigue and highway safety
Fatigue to is a critical problem for drivers and the trucking industry. Safe vehicle operation requires sustained vigilance, excellent judgment, and quick reactions, particularly during heavy traffic or poor driving conditions. Fatigue impairs all of these abilities, endangering not only truck drivers, but also other motorists who share the road with them. A common proximate cause of fatigue among truck drivers is partial sleep restriction, which in turn causes sleep debt and semi- chronic sleepiness. One study reported that drivers slept an average of only 4.78 hours per day, while those who worked on a steady night schedule averaged only 3.83 hours of sleep per day.
Sleep restriction, in turn, stems both from medical problems such as sleep apnea and from employment conditions in trucking. Long work hours cut into time available for sleep, and work-related stress makes it hard for drivers to sleep even when time is available. Shift work or an irregular work schedule forces many drivers to sleep during the day, in opposition to natural circadian rhythms, and most team drivers probably experience this irregular schedule. Sleeper berths do not provide optimal sleeping conditions, and sleep likely is fragmented for solo drivers and team drivers alike. Some drivers find it difficult to sleep in a moving vehicle, especially if they do not trust the driving ability of their partner, or if the vehicle is making numerous stops. Likewise, solo drivers' sleep may be fragmented while awaiting notification of the availability of their next load.
​
Even moderate levels of sleep deprivation (17-24 hours of wakefulness) can cause neurobehavioral impairment equivalent to a blood alcohol level (BAC) of 0.05 to 0.10. This is considered an unsafe level of functioning for truck drivers; commercial drivers may have their licenses revoked if they operate a heavy truck or haul hazardous cargo with a BAC of 0.04 or above. Further compounding the problem, a driver may not be aware of his or her level of impairment for two reasons: (1) over several days of sleep restriction, habituation may make sleepiness feel normal to the driver, and (2) “wake state instability” causes individuals with moderate sleep loss to perform optimally most of the time, but not reliably. Thus, while sleep-deprived individuals do not necessarily experience any immediate impairment of neurobehavioral function, lapses can occur when sustained cognitive accuracy and speed are critical.
​
The inability to determine their level of impairment may explain why some drivers are willing to risk driving while fatigued. In the U.S., 25% of long-distance truck drivers reported falling asleep at the wheel in the past year, while 47% reported having fallen asleep at the wheel sometime during their driving career. Drivers were more likely to report falling asleep at the wheel if they split their off-duty periods, or if they worked a demanding schedule (10 or more hours of consecutive driving, or less than 8 hours of off- duty time per day). Similarly, Australian truck drivers reporting 6 or fewer hours of sleep prior to a trip were significantly more likely report a hazardous event related to fatigue during that trip, such as nodding off while driving. According to conference participants, driver fatigue was a factor in 6% to 49% of the highway truck crashes they studied.
​
Other health effects of driver work hours
In addition to increasing the risk of being in a crash, the long and irregular work hours of many drivers can have other adverse health effects. Sleep debt is associated with impaired glucose metabolism, abnormal cortisol (stress hormone) regulation, altered growth hormone (GH) profiles, altered autonomic function (elevated sympathovagal balance), and impaired immune function. Disruptions in the endocrine system may contribute to health problems such as obesity, diabetes, and hypertension. Long-haul drivers who work many hours per day and do not have 24-hour work/rest cycles may suffer from desynchronized internal circadian rhythms. Working over 40 hours per week can double the risk of acute Helicobacter pylori infection (associated with peptic ulcers), even controlling for age, sex, and marital status. Irregular hours and night work raise the risk of being hospitalized for ischemic heart disease (IHD), and professional drivers are at greater risk of IHD if they work long hours.
​
The demanding work schedule of truck drivers also makes it more difficult for them to obtain quality health care. Forty-seven percent of long-distance truck drivers surveyed lacked a regular health care provider. Fifty-six percent of drivers found it difficult to make a healthcare appointment when at home due to their work schedule, and 62% said they had failed to seek out needed health care when on the road working.
​
Stress
Truck drivers experience stress from many sources. Long working hours, night work, or spending extended periods on the road away from friends and family can isolate drivers and leave them too exhausted to nourish their relationships. Pressure to stay on schedule even when road conditions are bad or they are fatigued can strain drivers’ nerves. Delivering or picking up loads can be taxing – drivers are often required to wait in their trucks for long and unpredictable periods of time; they may be denied opportunities for food, water, and restroom facilities; and they may be treated disrespectfully by shipping and receiving personnel. Owner-operators are often under intense financial pressure, finding it difficult to make the required loan or lease payments on their truck due to low compensation rates.
​
Workplace violence
Truck drivers can be victims of either physical violence or verbal abuse. Among 300 Australian truck drivers surveyed, 30% had been victims of verbal abuse, 21% had been victims of “road rage,” 10% had been threatened, and 1% had been assaulted. At freight forwarding yards, verbal abuse and threats were closely linked with economic pressures in nearly all incidents. Loading delays, drivers cutting in line, and mistakes by forklift drivers fueled tensions and led to the violent behaviors. U.S. beer delivery drivers are robbery targets, since they may carry $1,000 to $3,000 in cash by the end of the day. Threat of such abuse and violence can increase psychological stress and use of maladaptive coping mechanisms.
​
Driver Compensation and Safety
Driver compensation is inversely associated with both employee turnover and crash risk. Three empirical studies on the relationship between truck driver compensation and safety found a strong and significant relationship: more pay to the driver resulted in substantially fewer crashes. In a study of J.B. Hunt drivers, researchers found a 10% higher base mileage rate was associated with a 34% lower probability of a crash. In addition, a 10% increase in driver pay was associated with a 6% lower crash probability, giving an overall pay-rate effect of 1:4. In a cross-sectional study of 102 truckload carriers, researchers found that for every 10% increase in average total compensation for drivers, the carrier would experience a 9.2% lower crash rate. In a driver survey study, researchers found that drivers earning a 10% higher mileage rate had an 18.7% lower probability of having a crash during the reporting year, while drivers given 10% more paid days off had a 6.3% lower probability of having a crash during that same year.
​
Higher compensation may reduce crash risk by enabling carriers to recruit and retain better-qualified drivers. For example, unionized LTL carriers provide good pay (typically $60-70,000 per year for drivers), pensions, and health insurance benefits; drivers at these companies tend to have long job tenure, sometimes staying at the same company for 30 to 40 years. In addition, higher compensation might reduce the driver’s economic incentive to exceed legal and safe driving limits while increasing his or her desire to maintain a good driving record.