Motorcoach Industry Hours of Service and Fatigue Management Techniques (2005)

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

7CHAPTER 2 STATEMENT OF THE PROBLEM: FATIGUE AND TRANSPORTATION EQUIPMENT OPERATORS In the United States, in recent years several studies (NCSDR/ NHTSA, 1998; Johnson, 1998; Reissman, 1996) produced var- ious estimates of the level of sleep-related road accidents. The National Highway Traffic Safety Administration (NHTSA) estimates that there are 56,000 sleep-related road crashes annually in the United States, resulting in 40,000 injuries and 1,550 fatalities (NCSDR/NHTSA, 1998). However, specific motorcoach data are not identified in these studies. Studies in Great Britain (Horne and Reyner, 2000), Australia (Fell, 1994), Germany (Hell, 1997), New Zealand (Land Transport Safety Authority, 1998), Norway (Sagberg, 1999), and Israel (Zomer, 1990) all identified vehicle operator fatigue as a significant contributor to road crashes. Even in such overviews of the international driver safety research commu- nity, no specific data about motorcoach operators were found. The Department of Transportation/Research and Special Programs Administration (McCallum et al., 2003) sponsored a report that associated many factors with transportation operator fatigue. The RSPA report describes several general operational fatigue risk factors identified during structured interviews with representatives from the airline, railroad, mar- itime, and trucking industries. When these risk factors are pres- ent, there is an increased likelihood that operators are working with compromised alertness and possibly even in a state of fatigue. The McCallum et al. (2003) report is the primary source document for the following discussion of many factors that contribute to transportation operator fatigue; many of these pertain to commercial bus and motorcoach operators as well. EXTENDED WORK AND COMMUTING PERIODS Most commercial transportation operator work hours are regulated by Federal HOS rules. Therefore, long work hours seldom—independently—result in operator fatigue. Rather, it is the combination of long work periods and other non-duty factors that contribute to on-the-job fatigue, by limiting the available time for recreation, rest, and sleep. Over extended working periods, repeated inadequate sleep periods can result in accumulated sleep debt and associated operator fatigue. Among the primary aspects of extended work and/or com- muting periods that have been cited as contributing to opera- tor fatigue are • Long commutes to or from work on a daily basis, • Long waits after reporting for work before duty begins, • Forced interruptions in work that extend the duty day, and • Long commutes from home to report for work prior to beginning a multi-day work period. WORK SCHEDULES Split-Shifts Split-shift work can increase the likelihood of operator fatigue, by resulting in schedules that are not conducive to obtaining adequate sleep. Among the primary factors that commonly occur in conjunction with split-shift schedules contributing to operator fatigue are • Early morning start of shift; • Late evening end of shift; • High-paced operations during the work period; • Limited time at home during the awake period; • Difficulty in taking advantage of mid-day sleep oppor- tunities; and • Sleep/work periods conflicting with circadian rhythm. When work schedules require people to obtain their sleep during times that are normally awake periods, the quality and quantity of sleep suffers. Work during “low” periods of the circadian rhythm (roughly 1 a.m. to 4 a.m. and 1 p.m. to 4 p.m.) can be associated with drowsiness and a low level of alertness. Inappropriate times to obtain sleep include • Late morning (for those adjusted to a nighttime sleep schedule); • Afternoon (for those adjusted to a nighttime sleep schedule); • Early evening (for those adjusted to a nighttime sleep schedule); and • Any shift in sleep time due to time zone travel that requires sleep during the day at the origin of travel (i.e., the jet lag phenomenon).

Local night routes and cross-country routes often involve nighttime driving and daytime sleeping. Night drivers com- monly shift to daytime schedules on weekends or days off, resulting in weekly disruption of their usual sleeping period. HOS rules can require an off-duty period that is not conducive to sleep (e.g., 4 p.m. to 2 a.m.), resulting in low-quality sleep immediately followed by a driving period beginning during a “low” circadian period (i.e., 2 a.m.). Changing or Rotating Work Schedules Many commercial transportation operations require fre- quent changes or rotations in schedule. These schedule shifts lead to relatively quick changes in the time of day at which operators can obtain sleep, generally resulting in inadequate levels of rest. Changing or rotating work schedules can be characterized as follows: • Changes in work and rest schedules that do not have a fixed pattern and thereby result in fatigue management challenges that are extremely difficult to address, and • Rotating schedules that have fairly systematic shifts in the work start and stop times. Unpredictable Work Schedules The amount of advance notice commercial transportation operators receive regarding their work schedule varies sub- stantially. An unpredictable schedule can lead to forced changes in sleep times and therefore to low-quality sleep. Unpredictable schedules can also cause workers to wake sooner than necessary in order to check in with dispatchers. Conditions commonly associated with unpredictable work schedules include • Being “on call” for work without a fixed schedule; • First-in, first-out work pool scheduling; and • Schedule delays resulting from equipment, weather, or traffic problems. LACK OF REST OR NAP PERIODS DURING WORK Taking a brief rest or nap during a work period is a con- troversial topic in some transportation settings, while it is considered the procedural norm in others. Research has demon- strated the value of planned napping to supplement main sleep obtained and to temporarily restore alertness on the job. Lack of rest or nap periods can result from • Company policies that restrict or prohibit napping, and • Unwillingness of operators to take naps. 8 SLEEP DISRUPTION Interruptions to or disturbed sleep can make returning to sleep more difficult. It has been shown that both the number and timing of disruptions can adversely affect daytime alert- ness. Some general factors that disrupt sleep in commercial transportation operations include • Noise, vibration, movement, uncomfortable temperature, and poor air quality in sleeping quarters; • Unfamiliar environments away from home with less than optimal conditions; and • Attempting to sleep at an inappropriate time for one’s circadian rhythm. INADEQUATE EXERCISE OPPORTUNITIES People who exercise regularly have fewer episodes of sleep- lessness. Isolated exercise, while not an effective countermea- sure for immediate fatigue, can improve sleep quality by promoting smoother, more-regular transitions between the cycles and phases of sleep. Moderate exercise lasting 20 to 30 minutes, three or four times a week, promotes sleep. Exercise in the morning or afternoon is preferred, because exercise close to evening bedtime can disrupt the onset of sleep. A brisk walk can be very beneficial, although more vigorous exercise has been shown to provide increased health benefits. Even exer- cises designed for environments with restricted space (e.g., inside a truck sleeper berth) have also been shown to be bene- ficial. Factors that may limit exercise opportunities include • Personal habits that might need to be overcome in initi- ating an exercise program, • Work schedules that might need to be adjusted to include appropriate exercise opportunities, and • Travel or living conditions that can limit access to exer- cise equipment or space. POOR DIET What one eats can be a determining factor in sleep quality and duration. Some dietary behaviors that can disrupt sleep include • Eating heavy or spicy foods just prior to bedtime, which can interfere with sleep by causing heartburn; • Consuming alcohol just prior to bedtime can induce sleep initially, but tends to lead to fragmented sleep; and • Consuming caffeine within 4 to 6 hours before bedtime can delay the onset of sleep as well as disrupt sleep. ENVIRONMENTAL STRESSORS Several environmental factors can adversely affect a com- mercial transportation operator’s level of alertness. These

include environmental aspects related to heat, humidity, cold, altitude, vibration, and noise. Heat and Humidity Generally, one experiences high ambient temperatures as dry heat (temperature above 85°F, humidity less than 50%) or wet heat (temperature above 85°F, humidity above 80%). All excessively hot conditions make operators feel less alert and generally more fatigued. Hot-wet working conditions can be significantly more detrimental to worker performance than can hot-dry conditions and will usually make one feel “fatigued” much sooner than will temperatures less than 75°F. Cold Cold weather can indirectly contribute to operator fatigue. Operators often wear several layers of clothing during cold weather, which can make using restroom facilities more dif- ficult, which in turn can lead operators to reduce the amount of liquids they consume. Reduced liquid consumption can then lead to dehydration, which can cause operators to become fatigued more quickly than usual. High Terrestrial Altitude Driving at altitudes in excess of 5,000 feet can increase a driver’s respiration and heart rate; and sleeping at high altitude can result in blood pooling in the arms and legs. Spending even a few hours at high terrestrial altitude (e.g., mountainous passes) can cause the general malaise and discomfort that accompanies Acute Mountain Sickness (AMS). These effects dissipate as one acclimates to a higher altitude, usually in a matter of a few days. 9 Drivers should be aware of the effects of high altitude, and, if at all possible, should avoid sleeping at high altitudes (e.g., above 5,000 feet). Whole Body Vibration Whole-body vibration and acceleration accompany opera- tion of several types of transportation vehicles, including air- craft, helicopters, large trucks, buses, trains, ships, and small vessels. Operation of helicopters, automobiles, trucks, and buses exposes operators to increasing acceleration magnitudes, with a frequency range extending up to 100 Hz, depending on the roughness of the air/road/seas and the vehicle speed. Although most operators consider these to be lower-level fatiguing effects, they can add to operators’ general feeling of fatigue, thereby compromising their alertness while oper- ating equipment, especially if they are exposed to these effects over long duty days. Acoustical Noise Operators are exposed to engine noises in all transportation vehicles, as well as related noises emanating from controls, transmissions, braking systems, and wind streams. Some of these noises present more of a hearing-conservation issue than a driver fatigue issue. In fact, wearing ear protection in the presence of these noises is often called for; however, these noises can also contribute to an operator’s level of fatigue. The continuous “hum” and other intermittent noises of most run- ning engines, especially in hot and stuffy crew compartments, can contribute to sleepiness on lengthy trips. Being aware that noise can contribute to one’s overall feeling of operator fatigue is an important step toward ensuring that operators take rest breaks.