National Academies Press: OpenBook

Crew Size and Maritime Safety (1990)

Chapter: 2. Safety Experience with Smaller Crews

« Previous: 1. Introduction
Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Suggested Citation:"2. Safety Experience with Smaller Crews." National Research Council. 1990. Crew Size and Maritime Safety. Washington, DC: The National Academies Press. doi: 10.17226/1620.
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Safety Experience with Smaller Crews Recent reductions in crew sizes aboard Asian and northern European vessels have been preceded by extensive government sponsored programs to define, through careful step-by-step experimentation, the potential op- erational impacts. In the United States, less significant reductions in crew sizes and discussions of further reductions have been met with legitimate concern about their impact on maritime safety. However, the United States has not seen a comparable effort by government, industry, and labor to address this concern through comprehensive analysis and experimentation. Safety concerns expressed over crew reductions relate primarily to three operational considerations. 1. Fatigue: Will there be greater demands placed on the remaining crew members, and if so will there be a reduction in alertness negatively impacting safety of the ship or its crew? Or, will the overall impact of changes hold even or reduce working hours and/or fatigue levels for the remaining crew? 2. Training: With the higher degree of automation (often used to jus- tify crew reductions), will the remaining crew be able to handle emergencies if automated systems fail? Are higher or different levels of competence required? Will the crew be adequately trained for the new conditions? 3. Maintenance: Will crew reductions result in the neglect of essential maintenance? To what extent will better equipment, more durable coatings, riding maintenance crews, and other measures compensate by improving the reliability of equipment? 15

16 CREW SIZE AND MARITIME SAFETY Lack of attention to these problems will raise the risk of injuries and vessel accidents with attendant social, economic, and environmental costs. The U.S. Coast Guard, as the regulatory body charged with protecting the public interest in such matters, has addressed these questions each time it has been asked to set or revise the minimum manning levels specified by a vessel's Certificate of Inspection (COI). To make these judgments requires an objective and stable regulatory framework based on adequate safety statistics and a clear understanding of the automation technologies now being installed. The Coast Guard must also take into account variations from ship to ship and from operator to operator. The nation's and the world's fleets are highly varied. Manning practices that are acceptable aboard a well- managed, well-maintained ship with a well-trained crew and appropriate automation and safety equipment may be unacceptable aboard a vessel without these advantages. These regulatory judgments are especially challenging where the Coast Guard must carry out its responsibility to prevent unsafe practices by foreign-hag vessels in U.S. ports. Some flags have much higher casualty rates than others (Ponce, 1990~. (The United States, despite its aging fleet, has one of the better safety records in this regard.) Although the Coast Guard has legal authority to inspect foreign-flag vessels for any and all safety deficiencies, the agency in practice does not object to manning practices that conform to vessels' flag state requirements (see Chapter 5~. Accidents are discrete events that are often highly visible and readily recounted as evidence of declining safety. Public concerns raised by them are often valid and may be difficult to respond to. Less evident and certainly less prone to publicity are the data relating to safety performance over an extended period of time and across a broad spectrum of operations. Over the past 20 years, the industry has experienced a general improvement in its casualty and personnel injury rates. While not perfect in either comprehensiveness or standardization of reporting format, such data are currently the best indicator of whether safety regulations and systems to promote or improve safety are achieving their intended objectives. Unfortunately, however, the available data bases on casualties, acci- dents, and oil spills do not readily yield information on crew sizes of the vessels involved. A clear understanding of the safety record of smaller crews will require first a substantial data collection effort—an effort that was be- yond this committee's means. In the future, the proprietors of the data bases should take steps to ensure that they capture crew size information.

SAFETY EXPERIENCE WITH SMALLER CREWS THE PROBLEM OF QUANTIFYING MARITIME SAFETY 17 The problem of assessing maritime safety goes beyond the lack of crew size data. Determining the overall safety impacts of moves toward smaller crews requires estimating not only the associated marginal increase or decrease in the frequency of casualties, accidents, and environmental pollution incidents, but also the impacts of those events on people, property, and the environment. The information on which to base such an assessment is subject to great uncertainty. It is at present inadequate for development of sound conclusions. The most fundamental problem is that the impacts of casualties, per- sonnel accidents, and environmental pollution incidents are highly varied, and thus difficult to assess and compare. Property damage, environmental damage, and human pain or death are very different things. Assessing and comparing impacts of maritime safety lapses must therefore be largely subjective. In practice, regulatory priorities of this kind are established by policy decisions, reflecting the values society places on the various potential losses involved. The frequency of such incidents, in contrast, are quantifiable, given adequate information. Several organizations maintain records of these events both domestically and worldwide. For example, data on the numbers of casualties, personnel injuries, and oil spills per year are easily obtained. However, this information by itself is inadequate for meaningful statistical estimates of the contributions of vessel manning to the safety record. First, the available data bases do not include information on vessels' manning in computer-searchable form. In addition, they do not generally offer information on the many other variables and causal factors that interact to determine the safety record of an individual vessel. Management practices (e.g., maintenance, training, and schedulingy, extent of compliance with regulatory requirements, the performance of those entrusted with operating and navigating vessels, and the service to which the vessel is put (its trade and routes); all must be known or statistically estimated before the causal role of manning in safety performance can be assessed. Finally, there is no general agreement on an appropriate measure of exposure to hazards. Casualty and accident data must be related to an exposure variable. One obvious approach might be to compare the per- centage of a given flag's (or a given fleet's) tankers experiencing accidents to the corresponding percentage of the worldwide fleet experiencing the same class of accidents. However, this comparison may be misleading, since tankers of different flags may have markedly different services and routes, thereby encountering different hazards. Studies thus far have used at least three approximations of exposure to hazards: port calls, tons delivered,

18 CREW SIZE AND MARITIME SAFETY and ton-miles. These measures yield very different estimates of accident frequencies and can yield different rankings of rise For example, as tanker size increases the rate of accidents and pollution incidents increases when tabulated by port call, but decreases when tabulated by ton of cargo deliv- ered (Meade et al., 1981~. Furthermore, collection and analysis of exposure data is not routine; obtaining and working with it can be time consuming. Development of maritime exposure data bases is required. Accurate maritime safety assessments require precise, reliable, and highly detailed data on vessels, casualties, accidents, and pollution incidents. In addition, identifying trends requires intimate knowledge of the validity and variability of data from different sources and complex multivariate analysis. At present, such a treatment cannot be supported by the available data and analytic methods. Lack of Reliable Data The committee attempted to assess the possible effects of smaller crews on ship safety by analyzing data gathered and maintained by the U.S. Coast Guard, Lloyd's Register of Shipping, shipping companies, and industry organizations. It compiled records of reported ship casualties and personnel injuries from these sources and tried to relate these to information on crew size. Unfortunately, it became apparent that no adequate body of such data is available in the public domain. Neither government nor industry has collected and maintained accident and casualty data that can be readily paired with that on crew size, training, or organization. Developing such data in the future will require a worldwide initiative to record crew information with every report of a casualty or accident and to store the information in such a way that researchers can analyze it. The most important obstacle to this attempt was the fact that none of the maritime casualty data bases has crew size coded to allow tabulation of records on this basis. For example, although the Coast Guard's form for "Report of Marine Accident, Report of Death (CG-2692~" provides for the entry of the number of persons on board, this information is not recorded in the ship casualty (CASMAIN) and pollution incident (FIRS) data bases that the Coast Guard uses to access accident data. (In fact, a manual review of the raw accident reports revealed that more than one-fourth of the reports provided no indication of crew numbers.) Lloyd's Register of Shipping does not collect crew size data in any of its ship or casualty records. The Marine Index Bureau comes closest to providing the desired information. Owing to its billing policy, this private agency has crew size data for each member company's ships. This admin- istrative feature theoretically would allow the agency to correlate member companies' reported shipboard accident data with crew size. However,

SAFETY EXPERIENCE WITH SMALLER CREWS 19 the requirement of strict anonymity of the reporting companies and crews precludes follow-up analysis of such data. An adequate analysis of maritime safety, in the committee's view, requires the direct comparison of safety data for similar ships being manned at low and higher levels. Such comparisons within an operator's own fleet, or on the same ships at different times and different levels of manning, seem most appropriate, since they avoid attributing to manning safety differences that may be due to other factors, such as management, maintenance support, or operating conditions. Minimally, comparisons should be sought that ensure that high- and low-manned ships from different fleets are matched by size, age, trade, nationality, shore support, and operating costs. An excellent, albeit limited, example of the kind of comparison to be desired is the case, discussed more fully below, of a 16-vessel containership fleet whose operator collected consistent personnel injury data over six years during which crews were reduced from 34 to 21. During this period, the annual rate of injuries per crew member remained stable. While this isolated case demonstrates the possibility of making meaningful statistical assessments, it is grossly insufficient as a basis for general conclusions. Comparable data covering a broader range of casualties and accidents and a larger cross-section of the world's fleets are needed. Because the vast majority of marine casualty data are incomplete and unsystematic compared with the previous example, the committee conducted limited trial investigations of existing data to determine whether the influence of crew size could be studied in a practical manner. In one trial, a small sample of vessels known to be operated with crews of 20 or fewer was extracted by name from the U.S. Coast Guard's data bases (including the Coast Guard's copy of the Lloyd's Register files). Information was obtained on reported spills and hull or machinery failures for 20 U.S. tankers and integrated tug-barges (ITBs) between 1975 and 1987. Although the average incidences of spills and failures per ship were obtainable, there was no basis of comparison for crew-size effects. It was impossible to determine the total number of vessels of these types that entered U.S. waters (thus subject to reporting requirements) and therefore impossible to estimate the average frequency of spills or failures for all ships regardless of crew size. As a consequence, there was no baseline for comparison. In addition, the reliability of the data bases came into question. The FIRS file data on ITBs, for example, included inconsistent vessel identification numbers, making it difficult to determine whether the vessel name search was yielding all data for each vessel. In a second trial, the committee attempted to derive a broader sample by searching the data bases by company name, using companies known to operate with small crews. It was learned, however, that the CASMAIN and

20 CREW SIZE AND MARITIME SAFETY Lloyd's data bases cannot be searched reliably by company name. As an alternative, a committee task group made . manual search of the Lloyd's data base by looking up a sample range of ships operated by eight foreign- flag companies reported to use small crews. All of each operator's ships between 19,000 and 30,000 gross registered tons were selected (a total of 51 ships), and casualty data was retrieved from the data base by vessel name. Each vessel's length of service was used to compute the overall fleet incidence of casualties and accidents. The result, for a total of 448 ship-years, was only 13 reported accidents, an average annual rate of 0.0266 per ship. Again, as with the results summarized above for ships known to operate with small crews, there is no basis for comparison with larger crowed vessels. Furthermore, the result is an order of magnitude smaller than that obtained from the analysis of individual ships, suggesting that selection by fleet may introduce vessels that are out of service during some of the reporting period or that casualty reporting outside U.S. waters is less reliable. Thus, the committee could not conduct a complete statistical analysis of the effect of vessel manning on safety performance. Existing U.S. and international maritime operations data are simply insufficient for deriving valid statistics about the safety of smaller crews. Further research in this area, supported by improved record-keeping worldwide, is essential. Improving the Collection of Data At present, the most comprehensive and detailed data on the safety of vessels with smaller crews is in the files of individual companies. All U.S.- flag operators could be asked to submit, on a confidential basis, whatever safety-related comparisons they maintain internally on their own vessels. Comparison and analysis of the safety indices used by different companies could then be undertaken, which would provide meaningful insights into current safety trends and additional factors that should be monitored. Out of such a review should come recommendations as to how present Coast Guard reporting requirements should be modified to include factors that help identify meaningful relationships between casualties and injuries, on the one hand, and possible causal factors (e.g., vessel age, vessel size, crew size, crew overtime, crew continuity, and vessel equipment) on the other. To make the most of its own data, the Coast Guard should revise its casualty and oil spill data bases to make them readily accessible for search information on the sizes and organizations of crews.

SAFETY EXPERIENCE WITH SMALLER CREWS INDUSTRY SAFETY INFORMATION 21 In general, as noted earlier, the broad industry-wide data contain no direct information on the crew levels of vessels involved in accidents. However, such data, collected consistently over the past few decades, are meaningful, since crew sizes have been substantially reduced during this time. Thus, these data may offer some general insight into the safety implications of smaller crews. This insight is clouded, however, by other developments over the same period, such as more stringent requirements for safety equipment and procedures. Though there are some variances, the available industry safety statistics indicate the following: . There has been a measurable and substantial improvement in the rate of both vessel casualties (accidents) and personnel injuries during the past 20 years. More specifically, there has been a declining rate of vessel casualties, a declining rate of vessel losses as a result of accidents, and a declining rate of personnel injuries. These trends are evident on a nondimensional basis (e.g., percentage of total vessels, percentage of total gross tonnage, incidents per ship, and injuries per seagoing employee), that is, as a result of a methodology that eliminates the impact of changes in fleet size, numbers of employees, and other variables. These trends are consistent whether one considers statistics published by the International Maritime Organization (IMO) of the United Nations, by Lloyd's Casualty Reports, by the Marine Index Bureau, or by the U.S. Coast Guard. · During the same 20-year period, the average crew size has declined substantially (from the low thirties to the low twenties for U.S.-flag vessels and to the high teens for many foreign fleets). While these two trends have occurred during the same time period, other factors have also changed. Technology has improved, operating procedures have been refined, and the scrutiny of maritime operations by government and industry bodies has increased. The safety data available from the various worldwide sources is not sufficiently detailed to correlate vessel casualties and personnel injuries with crew size. It is therefore not possible to isolate the effect of crew size to determine whether any causal relation, positive or negative, exists between crew size and safety. Neither is it possible to determine from the available data whether crew size, in itself, interacts with other variables to enhance or reduce safety. Lloyd's Vessel Loss Data Figure 2-1 displays worldwide total vessel loss rates over the past 20 years. During this period, the loss rate has dropped from about 0.65 percent to 0.32 percent per year a 50 percent decline. Although total

22 CREW SIZE AND MARrTIME SAFETY losses worldwide are a gross measure covering large and small vessels (individual years aside), the figure demonstrates that the combined impact of all factors including changes in the size and types of vessels sailing, ship design, manning, and operating practices has been to reduce total vessel losses substantially. In terms of tonnage (a more accurate indicator of commercial activity), a down trend is also evident (Figure 2-2~. Although there was an upturn in the late 1970s, over the past 20 years annual tonnage losses have declined 20 percent, from about 0.35 percent to 0.28 percent per year. Total losses of U.S.-flag vessels have also declined (Figure 2-3~. The total loss percentage declined from about 0.4 percent in the early 1970s to about 0.10 percent recently, a figure only one-third the world average given in Figure 2-1. Figure 2-4 shows no trend in U.S.-flag percent tonnage loss, but the average, about 0.17 percent, is only about two-thirds of the world average shown in Figure 2-2. The considerable year-to-year variance in the U.S. figures is due to the small number of data points and the influence of large vessels (e.g., the Manhattan in 1987) on tonnage percentages. Nonetheless, the lower U.S. loss ratios indicate that some factors are keeping U.S.-flag vessels ahead of the world in preventing total losses of vessels. These factors may include the types of vessels under the U.S. flag, the trade routes served, U.S. Coast Guard and American Bureau of Shipping requirements, and the quality of American seamen. Marine Index Bureau Injury Data Statistical data on injuries are issued annually by the Marine Index Bureau. Figure 2-5 shows that, over the past 20 years, the aggregate incidence of injuries per working seaman in U.S. deepwater vessels has declined by more than 40 percent, from about 0.45 to 0.25 injuries per year per seagoing employee. While this is a gross aggregation of data, it supports a conclusion that during the last two decades the net impact of the aggregate changes in the seagoing environment has been to reduce injury rates for seamen significantly. Tanker Casualty Data A subset of total vessel data is tanker data developed by the Inter- national Maritime Organization (IMO). These data cover tankers not in layup or storage and over 6,000 gross tons. Figure 2-6 shows that, after rising in the late 1970s, worldwide casualty rates of large tank vessels have declined to about 2.0 per hundred vessels, a level roughly 20 percent below those of the mid to late 1970s. The decline in the number of tankers lost (excluding war damage) is

SAFETY EXPERIENCE WITH SMALLER CREWS 0.80 - 0.70 co ~ 0.60 an ~ 0.50- o C' 0 40 - A: Z 0.30- LL c: 0.20- 0.10 - ~ 0.60 cn o u, 0.50- O 0 40 - co O 030 O 0.20 LU ~ 0.1 0 UJ C) rl on 0.80 Q % of Ships Lost 0.00- 1 ' 1 ' 1 ' I 70 72 74 76 78 80 82 YEAR 1 84 86 88 Gil I; 0 % of GRT Lost ~ ' 1 ' 1 ' 1 ' 1 ' 1 ' I ' I ' 1 ' 1 70 72 74 76 78 80 82 84 86 88 YEAR u, 0.70 ~050~ `~ I_ ~~< , 0.20- 0.10 - 0 % of Ships Lost 0.00- · ' 1 ' 1 ' I I ' ~ I · I · 1 70 72 74 76 78 80 82 84 86 88 YEAR <,' 0.60- o C' 0 50 - z o n o is: C' LL o LL z c' 0.40 - 0.30 - 0.20 - l 78 80 82 84 86 88 YEAR 0 % of GRT Lost Ad rid 0.10 ~ 0.00 1 I r- 70 72 74 76 23 FIGURE 2-1 Worldwide vessel loss rates (percentage of ships) for commercial ships, 1970-1988. The decline in the percentage loss of commercial ships since 1970 has been linear at a confidence level exceeding 99 percent. Souree: Data from Lloyd's Casualty Reports. FIGURE 2-2 Worldwide vessel loss rates (percentage of gross tonnage) for eommer- eial ships, 1970-1988. The decline in the rate of loss of commercial tonnage since 1970 has been nonlinear (power function) at a con- fidenee level exceeding 99 percent. Souree: Data from Lloyd's Casualty Reports. FIGURE 2-3 Total loss rates of U.S.-flag vessels, 1970-1988 (percentages of vessels). The decline in the rate of loss of U.S.- flag inspected vessels since 1970 has been nonlinear (power function) at a confidence level exceeding 90 percent. Souree: Data from Lloyd's Casualty Reports. FIGURE 2-4 Total loss rates of U.S.-flag vessels, 1970-1988 (percentages of gross ton- nage). The variation in the rate of loss of tonnage for U.S.-flag inspected vessels has exhibited a random behavior since 1970, which is best represented by an average value. Souree: Data from Lloyd's Casualty Reports.

24 `~> 50- he LL oh I o At: LL o o L11 a: I 3 - CO I 2.5 en to ° 2 LU ~ 1.5 - U} 0.5 - 28 ~ 24 - CO ~ 20 I LL 1 6 - UJ 12 - A) Q Z V 4 - . . O 1 , . . . . 70 72 74 76 0.9 . ~ 0.8 - I 0.7 _ 0.6 - 0.5 - Z 0.4 - <' 0.3_ 0.2 - 0.1 - O - . 70 CREW SIZE AND MARITIME SAFETY 40 n 30 20 10 O~ ....... 70 72 74 76 O Reported tor Yost 78 80 82 84 86 YEAR 3.5 - 0 Rate ox War Losses O - · I ' I · 1 · I ' I ' I 73 75 77 79 81 83 85 87 YEAR ~4 ~ 0 Fleet Size (1000s of vessels) ~ Lost (ox war loss) - O O O Or' 0 1 . ~ ~ · 1 ' 1 · 1 78 80 82 84 86 88 YEAR ~ ~ \ 0 Inspected Vessels 72 74 76 78 YEAR l 80 82 84 86 FIGURE 2-5 Annual injury rates per sea- going employee in U.S. deepwater vessels, 1970-1987. The decline in the injury rate for oceangoing seamen since 1970 has been linear at a confidence level exceeding 99 percent. Source: Data from Marine Index Bureau. FIGURE 2-6 Rates of serious casualties of oil tankers (actively trading vessels over 6,000 gross tons), 1974-1988. The decline in the rate of serious tanker casualties since 1970 has been linear at a confidence level exceeding 90 percent. Source: Data from International Maritime Organization. FIGURE 2-7 Numbers of tankers lost worldwide (excluding war damage), 1970- 1988. The decline in the rate of loss of tankers worldwide since 1970 has been linear at a confidence level exceeding 90 percent. Source: Data from International Maritime Organization. FIGURE 2-8 Reportable casualty rates of U.S.-flag ships, 1970-1986. Although there is a clear declining trend in the rate of casual- ties for U.S.-flag inspected vessels, the best estimation (nonlinear) correlates at a confi- dence level of less than 80 percent. Source: Data from U.S. Coast Guard, Annual Sta- tistical Summary.

SAFETY EXPERIENCE WITH SMALLER CREWS 25 even more striking, as shown in Figure 2-7. Peaks occurred in the late 1970s, but total losses have since declined to half the prior levels, perhaps indicating that safety measures adopted by IMO (such as requirements for flooding crude tankers' tanks with inert gas) are having the desired effect. U.S. Coast Guard Annual Casualty Reports Information has also been developed from the Coast Guard's Annual Statistical Summary of casualties and personnel injuries on inspected U.S.- flag commercial vessels. Based on these data, reportable casualties per ship have declined from about 0.8 incidents per vessel per year in the early 1970s to 0.6 recently (Figure 2-8~. Tanker incidents per vessel (Figure 2-9) seem to have held fairly constant in the 1.0 per ship per year range, with yearly variations as high as 1.4 and as low as 0.8. Correlated to tonnage, however, marked declines of over 20 percent for all vessels and 50 percent for tankers have occurred (Figure 2-10~. Oil Spill Data U.S. Coast Guard data for 1975 through 1989 were reviewed for ascer- tainable trends. Figure 2-11 shows that the absolute number of reported oil spills from barges, tankers, and all vessels has been declining. The number of barge spills exceeds tanker spills every year. Spills from vessels have also been declining as a percentage of total spills into water, which have also been declining (Figure 2-12~. However, this favorable trend is not reflected in the data on volumes spilled. Figure 2-13 shows that spill volumes may vary greatly from year to year and have not changed greatly during the period reviewed. In this regard, note that, although barge spills are usually small, in 8 of 12 years the total volume spilled from barges exceeded the volume spilled from tankers. In addition, large tanker spills may double or triple the volume of oil spilled from vessels in a year. When such large spills occur, vessels account for upwards of 75 percent of oil spilled from all sources, compared with about 35 percent in nonpeak years. Thus, while emphasis on oil spill prevention may have reduced the number of spills in recent years, the total volume spilled in any year fluctuates greatly. Individual Company Data The committee was able to obtain some safety data from individual operators that have reduced their crews. Figure 2-14 shows trends in the number of billets, casualties, material failures and breakdowns, and personnel injuries and fatalities per ship for Company A during three-year

26 1.4 - 1.2 - I 1 - ~n ~ 0.8 - CL in z 0.6 - LL - c, 0.4 an 0.2 0.07 CO O 0.06 C) .t 0.05 CO O 0.04 ~ 0.03 U. 0.02 z (, 0.01 o 4.5- re 4 1~ 3.5- Ct 3 ~ 2.5 o z 2 1.5 u' 1 - O 0.5 m °- z AJAR O Tankers (per USCG) .. O~ . .. 70 72 74 76 78 80 YEAR 82 84 86 ~ 4 0 Tankers (per kDWT) <0 All Ships (per kGT) 70 72 74 76 78 80 82 84 86 YEAR All Vessols :~ G. Tankers A Oil Barges ' 1 — 1 - I ' I ' I ' I ' 1975 1977 1979 1981 1983 1985 1987 1989 YEAR in 1 0 ~ 9- CO J 8 o7 ,~ 6 UJ ~ 4 (A 2 ~ 1 ~ \ Tankers OI Barges AN / 1 ·,4] O- . , . , . I . , . I · I ' 1 1975 1977 1979 1981 1983 1985 1987 1989 YEAR CREW SIZE AND MARfTIME SAFETY FIGURE 2-9 Reportable casualty rates of U.S.-flag tank ships, 1970-1986. Although there is a clear declining trend in the rate of casualties for U.S.-flag tankers, the best estimation (nonlinear) correlates at a confi- dence level of less than 80 percent. Source: Data from U.S. Coast Guard, Annual Sta- tistical Summary. FIGURE 2-10 Reportable casualty rates of U.S.-flag ships per thousand gross tons (up- per curved, and U.S.-flag tank ships per thou- sand deadweight tons (lower cume), 1970- 1986. In contrast to the low confidence in the correlation of the decline in casual- ties to the numbers of U.S.-flag commercial ships and tankers (Figures 2-8 and 2-9), the correlation to tonnage is very strong. For all vessels, the decline has been nonlinear (power function) at a confidence level ex- ceeding 90 percent; for tankers, it has been exponential at a confidence level exceeding 99 percent. Source: Data from U.S. Coast Guard, Annual Statistical Summary. FIGURE 2-11 Number of reported oil spills from (of all vessels, (o) tankers, and (~ oil barges, 1975-1989. Data for 1987-1989 are preliminary only and should be used with ~caution. Although there appeals to be a declining trend for the rate of oil spills by all vessels, the best estimate for this trend correlates at a confidence level of less than 80 percent. Source: Data from U.S. Coast Guard. FIGURE 2-12 Percentages of total reported oil spills from tankers and oil barges, 1975- 1989. Data for 1987-1989 are preliminary only and should be used with caution. Me variation in the percentages for barges has been essentially random and is best repre- sented as an average value equal to 8.02 percent. In contrast, the exponential decline in the percentage of spills from tankers cor- relates at a confidence level exceeding 99 percent. Source: Data from U.S. Coast Guard.

SAFETY EXPERIENCE WITH SMALLER CREWS 12 1 1 10 9 8 - ~ 7 LL J in LL J o 6 5 4 3 2 o _ 27 Tankers Oil Barges 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 YEAR FIGURE 2-13 Volumes of oil spilled by tankers and oil barges, 1975-1989. Source: U.S. Coast Guard. 3 AL elm . co a, ~ O I in llJ z LL — 1 LU Z — Z I LL - <5: C: o z o - - - - 1 Billets/Ship Yr MATE Fail/Ship Yr - E~ CAS/Ship Yr ~ INJ&FAT/Ship Yr l 1 . 1 - 1 ~.. :: .2 :-:- ~ :-:-: · :-.:-.: _ ... · : : ~ ..... i'.],, 1973 40 30 UJ on 20 LL G 10 976 1979 1982 1985 1988 YEAR o FIGURE 2-14 1tends in numbers of billets, casualties, material failureslbreakdowns and personnel injuries/fatalities per ship for Company A during consecutive three-year intervals from 1973 to 19~ (indexed with 1973 = 1.0~. Source: Marine Board Survey.

28 CREW SIZE AND MARrTIME SAFETY intervals from 1973 to 19~. While injuries and fatalities have declined as manning dropped, ship casualties fluctuated around an average of 0.53 per ship year.) Data provided by Company B show marked declines in oil spills per vessel and personnel injuries per million man-hours worked (Figures 2-15 and 2-16~. Oil spills per vessel have declined 45 percent in the last 15 years, and injuries per million man-hours worked have declined 50 percent. Since, as shown, the average number of employees per vessel in Company B has declined 30 percent (from 30 to 21) the absolute number of injuries per vessel has dropped 65 percent during the 15-year period. Another large operator provided personnel injury data on 16 company ships whose crews were reduced from 34 to 21 people. Average annual injury rates per crew member during the three years following the change were virtually the same as the three previous years. Safety Implications of Available Data The historical data, viewed from several perspectives, show that the rates of vessel casualties and personnel injuries have improved over the past two decades. These improvements have occurred simultaneously with a significant reduction in the average crew size. However, no direct link has been detected between crew size and vessel or personnel safety. The broad statistics should not be considered a basis for complacency. The limited data from individual companies show that safety records are not uniform, illustrating the truism that safety must be addressed by each company in terms of its specific operations. Except for those from Company A and Company B. none of the data discussed above provide specific information on manning practices. The data's importance stems from the known steady decline in average vessel manning, approaching 50 percent since World War II, due to the introduction of newer, more automated vessels with smaller crews and to manpower reductions on existing vessels. Some U.S.-flag ships have manning levels as low as 15 persons, while others have 25 or more. The larger crews are often on older vessels whose owners may not be convinced of the desirability of such automation or the certainty of payout on the required investment during the remaining life of the vessel. Replacements for older vessels invariably have more automation and lower required manning, so the trend toward lower average manning will continue. Foreign companies operate vessels with as few as 8 to 12 people. 1 The data on material failure in the figure represent days lost as the result of mechanical break- downs.

SAFETY EXPERIENCE WITH SMALLER CREWS 1.0 lL CO 0.8- > cr: lL 3 I In J o o a: LL m z 0.6 0.4 0.2 0.0 Lin Reg Oil Spills ___ Manning Per Vessel · —~__=— —a_ _ _ _ ___— _ ,, . ~ .. ~ ~ 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 29 -I 35 - 30 U] An U) UJ 25 O: 20 cD of z 1 5 <' LL 10 ~ UJ - 5 <: O FIGURE 2-15 Manning levels and annual rates of oil spills per vessel, Company B. 1974-1989. Ibe solid line is a linear regression fit to the data. 20 - <,' 1 8 o 1 6 cr: 1 4 o J - a; U] CO LL Z 2 Lin Reg InJunes ~~~ Manning Per Vessel o 35 An_ __ 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 30 Act In In 111 25 ~ a: UJ 20 c, z 15 <: 111 10 (9 LIJ 5 O FIGURE 2-16 Manning levels and annual rates of personnel injuries per million work- houm, Company B. 1974-1989. The solid line is a linear regression fit to the data.

30 CREW SIZE AND MARITIME SAFETY If they continue to operate safely, pressures will rise for the United States to follow suit. SAFETY CONCERNS Gross measures of performance provide few clues as to specific steps required to improve safety while further reducing manning. Safety factors and problems are best identified by the personnel involved, the licensed and unlicensed people working aboard the vessels, and the owners and operators. Accordingly, committee members and staff visited with unions and vessel operators to obtain their opinions and verify their concerns. Labor Organizations The committee solicited the views of maritime labor organizations representing licensed and unlicensed personnel serving aboard U.S.-hag vessels. At the committee meeting of September 13-15, 1989, spokesmen for 10 labor organizations described their safety experiences and concerns. Many also submitted written statements and other documents. Appendix C lists these spokesmen and the materials they submitted. Many union representatives believe safety has deteriorated with smaller crews. They point to increased fatigue due to longer working hours, poor maintenance practices, and fewer opportunities for on-thejob training. Some express a lack of confidence in the Coast Guard's even-handedness in addressing labor-management issues (Alliance of Independent Maritime Organizations, 1989; Hillman, 1989; International Transport Workers Fed- eration, 1990~. Vessel Operators The committee members and staff visited the offices of nine U.S.-owned vessel operators to conduct interviews (see Appendix D for questionnaire), and toured one vessel. The companies operate tank ships, tug-barge com- binations, bulk carriers, container ships, and special purpose ships, under both U.S. and foreign flags. Some, such as major oil companies, own their own ships, carry their own products, and hire their own crews. Others manage for other owners and hire from union rosters. Operators generally believe safety has improved aboard ships with smaller crews, owing to greater safety consciousness and improved equip- ment. They point out that crew reductions require better trained personnel who are able to accept more responsibility and to manage automated systems. Recognizing that elimination of most entry-level positions has reduced opportunities for on-thejob training, they believe they are taking

sAFEry EXPERIENCE WITH SMALLER CREWS 31 steps to ensure the necessary competence and thereby maintain or improve safety. Some operators cited fatigue and the difficulty of retaining key person- nel (especially junior licensed officers) as management challenges resulting from moves toward smaller crews. Most have made changes in maintenance practices to relieve crew members of some of their workload. Specific Safety Concerns More important than the general opinions expressed by labor and operators was the fact that they identified many common safety concerns. These concerns should be the object of efforts to further improve safety. Fatigue The potential for fatigue is the safety concern voiced most often and is taken seriously by labor and management. Both recognize that inattention can cause accidents. A few casualties have been attributed to inattention associated with fatigue. The recent World Prodigy grounding and oil spill near Newport, Rhode Island, is an example (National Transportation Safety Board, 1989~. Coast Guard casualty reports rarely note fatigue as a contributing factor; however, there is reason to believe that its contribution is under- reported, owing to reporting procedures (Pettin, 1987~. Complicating anal- ysis of the problem is the difficulty of measuring fatigue. Hours worked is at best a rough indicator, one which does not measure stress, the nature of the work performed, or the physical condition of the emnlovee (Pollard. 1990~. r ~ ~ Long working hours are common in the maritime industry, and indeed desired by many union members as a means of increasing their take-home pay. Since shipboard workers do not commute or cook their own meals, long hours may not be as tiring as they would be ashore. Where long hours are a recognized problem (e.g., the round-the-clock cargo responsibilities of deck officers or the heavy workloads imposed by frequent port calls), many companies employ personnel in excess of the minimums set by the Coast Guard to compensate for the increased work load. Others use shore-based personnel for cargo operations, so that crew members may rest. Little information is available to indicate the increase or decrease in working hours as crews have been reduced. Although some companies indicate that overtime has not changed significantly, some labor organiza- tions are genuinely concerned that smaller crews mean more hours worked, more fatigue for remaining licensed and unlicensed personnel, and there- fore degradation of safety. Management responds by saying that, properly managed, average working hours need not increase and that in some cases

32 CREW SIZE AND MARITIME SAFETY fatigue may decrease; for example, in engine rooms certified for unmanned operation, engine department personnel can work days only instead of standing four-hour on, eight-hour off watches. In a given situation, either point of view may be correct, depending on the degree of work planning and management of work effort. Maintenance Practices Traditionally, vessel crews have done most routine deck and engine maintenance. Newer materials and design changes have eliminated some of this work or made it a biennial shipyard repair item. Nonetheless, ship safety will be impaired if reduced manning causes deferral of needed maintenance on safety-related equipment. Union representatives have filed grievances alleging that crew reduc- tions have resulted in essential safety equipment being allowed to remain in disrepair in violation of Coast Guard regulations and collective bargaining agreements (Hillman, 1989~. Coast Guard personnel also have blamed crew reductions for maintenance deficiencies. In reporting a 1988 incident in- volving the simultaneous failure of electrical power and propulsion systems on a ship near the harbor entrance at Portland, Maine, the commander of the First Coast Guard District pointed out that the vessel's reduced en- gineering complement made adequate maintenance "impossible" (Folsom, 1988~. Furthermore, he stated, "Shoreside or riding maintenance crews look good on paper but are easily dropped, especially considering the eco- nomic conditions that currently plague the U.S. fleet." He expressed the opinion that "revalidation of reduced manning levels should be occurring with every Inspection for Certification." He noted that many chief engi- neers favor the licensing of electronics engineers to maintain automated systems. To avoid this potential problem while carrying smaller crews, some companies employ "riding crews" or repair firms to perform needed main- tenance in port. These approaches may be quite acceptable, but it remains incumbent on the companies to maintain records demonstrating compliance with Coast Guard regulations. Emergency Response Capacity Operators and unions agree that more attention to safety systems and emergency procedures will be necessary as crews are further reduced. Three general categories of emergency should be considered: First and perhaps most critical is the "all hands" type, such as fire and explosion, collision, or grounding. Vessel design and personnel training can help ensure the shipboard capability to evaluate and respond.

SAFETY EXPERIENCE WITH SMALLER CREWS 33 Preventive maintenance programs can help ensure that the vessel is in con- dition to operate properly and safely. Strict adherence to safety procedures (e.g., the use of fireproof doors in cargo areas) is also necessary. (Chapter 4 discusses a modeling exercise in which the personnel requirements for fighting an engine room fire are calculated.) Second, the vessel must be able to operate safely in case of power losses and failures of vital equipment such as steering gear, navigational equipment, mooring equipment, the main propulsion plant (including loss of automation and problems with diesel engines or boilers), and cargo gear. · Third is the ability to handle personnel casualties. Manning deci- sions must allow rapid and efficient response without depriving the vessel of its ability to operate. For example, evacuating a crew member by helicopter requires enough personnel to transfer the injured person (including at least four stretcher bearers) as well as enough to operate the ship. Rescues at sea presently involve at least six people in addition to those left aboard to operate the ship. Launching and retrieving lifeboats also can be labor intensive. Some operators and labor representatives interviewed stressed the im- portance of redundant safety systems (including internal communications equipment) capable of operation from several places on the vessel. Reduced Gaining Opportunities for Unlicensed Personnel The elimination of entry-level positions (such as wiper and ordinary seaman) on many vessels has reduced the opportunity for on-thejob train- ing, some of which is required for the more responsible positions that remain such as oiler and able-bodied seaman. Both labor and management personnel agreed that inexperienced or inadequately trained personnel can create safety problems, whether on watch, handling cargo, or operating emergency and safety systems. To prevent such problems, some companies have instituted "cadet" programs to train unlicensed personnel. Others hire in excess of the normal complement until crew members gain the necessary experience. Recent high unemployment in shipping has allowed some companies to meet their skill requirements by recruiting recent graduates of maritime academies (who are licensed officers) to work in unlicensed positions; the industry's expected upturn may limit that option. A few companies in recent years have negotiated labor contracts that provide for employment continuity among key personnel, thus ensuring that investments in additional training can be recaptured (see, for example, American President Lines, 1989~. Whatever the approach, it is essential that Coast Guard certifications be based on demonstrated proficiency and that management exercise diligence to promote or hire only qualified people.

34 Service Continuity by Crew Members CREW SIZE AND MARITIME SAFETY All operators agreed that continuity of service by crew members is an important safety factor, particularly with sophisticated shipboard systems requiring intimate knowledge. Repeated service aboard the same vessel ensures familiarity with the equipment and promotes teamwork. Continuity is most desirable among key personnel (master, chief engineer, chief mate, and 1st assistant engineer), and is helpful with junior officers and unlicensed personnel as well. One operator noted that crew levels of 9 to 11 would require 100 percent continuity. Physical Demands on Crew Members Concerns were also expressed about the growing need for physical fitness of crew members. Smaller crews mean fewer people available for emergency operations and very likely fewer physically strong people in situations where strength is needed. Assessments of minimum manning levels must take into account the degree to which labor-saving devices are available or tasks requiring strength have been eliminated. Several of those interviewed pointed out the desirability of designing vessels to minimize things such as unnecessary ladder climbing or heavy lifting to eliminate some of the causes of injuries as well as impediments to emergency response. Annual physical examinations were recommended by some operators. 1b be effective in improving safety more rigid standards of "fitness for duty" may need to be established and enforced. Changed Shipboard Social Conditions Recognizing that attitudes may affect alertness and attention to safety rules, several operators expressed concern over the impact of reduced manning on the shipboard social environment. With the smaller licensed and unlicensed groups and the breakdown of some of the traditional distinctions between the deck, engine, and steward's departments, new social structures will be necessary. Some companies are already promoting the ship's team concept, an effort that may be assisted by movement toward greater continuity of assignments. One operator, whose ships carry crews as small as 14 persons, reported that it had used psychologists from the beginning of its manpower reduction program. FURTHER RESEARCH Better information is needed on the relationship between crew size and safety experience. As noted earlier, the Coast Guard data bases are presently inadequate to support even retrospective conclusions about the

SAFEIY EXPERIENCE WITH SMALLER CREWS 35 safety records of U.S.-flag vessels that have reduced crews. Prospective regulatory judgments to support further reductions of crews rest on an even more inadequate base since the Coast Guard has not developed the human factors methods to assess such steps. In addition to the broad safety statistics, more detailed safety studies of the following factors are needed to support the manning innovations now being undertaken or contemplated by U.S.-flag fleets. Such studies should consider the following: the prevalence and severity of fatigue aboard merchant ships, with attention to the role of fatigue in navigation errors and personnel accidents; · the human factors issues presented by the one-person bridge, in- cluding the operators' responses to fatigue and the ergonomic design of control and monitoring systems; · changes in maintenance practices owing to reductions in engineer- ing complements; · the maintenance effectiveness of riding crews and shore-based maintenance; · the effects of traditional watch schedules on crew members' cir- cadian rhythms, and the consequent impacts on effectiveness and safety; and · the data collection requirements for adequate assessments of the safety effects of smaller crews. FINDINGS Rates of maritime casualties and personnel injuries, worldwide and in the U.S.-hag fleet, have declined steadily over the last two decades, at the same time that the manning of vessels has been reduced. While concerns about safety have been raised—including neglected maintenance, increased fatigue and stress, and lessened opportunities for on-thejob training- management, labor unions, and governments have addressed these con- cerns through training, qualification standards, and other management techniques. The committee did not find in its analysis of safety data or its contacts with industry and labor in the United States and worldwide any direct causal relationships between vessel manning levels and safety. Currently available maritime safety information is inadequate for mak- ing definite judgments about the contributions of various factors to maritime safety. While good information exists concerning numbers of casualties and the extent of damage, it is difficult to assemble information needed to cal- culate frequency of occurrence and assign the frequencies to different populations of ships (type, flag and age of ship, and numbers of crew). This information is needed to establish trends and make decisions about

36 CREW SIZE AND IL41UTIME SAFETY safeW. Information about the causes of casualties is also not uniformly assembled. Information on the prospective consequences of further reductions, which may involve substantial reorganizations of manning patterns, is also insufficient for firm judgments. The human factors studies to support increasing automation, for example, are only now beginning to appear, mainly in Europe. REFERENCES Alliance of Independent Maritime Organizations. 1989. The invasion of the sixty hour workweek standard and manning reductions in the U.S. Maritime Industry. Statement Submitted to the Committee on the Effect of Smaller Crews on Maritime Safety, National Research Council, Washington, D.C. September 14. American President Lines. 1989. Marine Operations Department training program 1990. Mimeo. Oakland, California. Commission on Merchant Marine and Defense. 1988. Third Report of the Commission on Merchant Marine and Defense. Washington, D.C.: U.S. Government Printing Office. Sept. 30. Folsom, D. L. 1988. Vessel automation control reliability, reduced manning, maintenance, and operator responsibility. Memorandum from Commander, First Coast Guard District, to Chief, Office of Marine Safety, Security and Environmental Protection, U.S. Coast Guard. Dec. 19. Hillman, John L. 1989. Letter from President, Exxon Seaman's Union, to Charles Bookman, Executive Director, Marine Board, National Research Council. September 21. International Transport Workers' Federation. 1990. Submission to the Eighth Session of the ILO/IMO Joint Committee on Staining (JCT8), Geneva, 17-21, September. Meade, N.F., R.C. Anderson, NJ. Goldberg, V.F. Keith, and R.M. Willis. 1981. An analysis of tanker casualties for the ten year period, 1969-1978. In Proceedings of the 1981 Oil Spill Prevention Conference. Washington, D.C.: Courtesy Associates. National Transportation Safety Board. 1989. Hearing record, joint NTSB-U.S. Coast Guard Marine Board of Investigation examination of Capt. Iakovas Georgoudis in the matter of the M/T World Prodigy grounding in Rhode Island Sound on June 23, 1989. Oct. 3. Perkins, M. R. 1988. Vessel automation control reliability, reduced manning, maintenance, and operator responsibility: First endorsement on MSO Portland's ltr 16711 of 6 Dec 88. Memorandum from Commanding Officer, Marine Safety Office, Portland, Maine, to Commandant, U.S. Coast Guard. Pettin, Thomas J. 1987. Fatigue as the cause of marine accidents, 1981-1985. U.S. Coast Guard, Marine Investigation Division. March. Pollard, J.K, M. Sterns, and E. D. Sussman. 1990. Shipboard Crew Fatigue, Safety, and Reduced Manning. Contract report for Office of Technology Assessment and U.S. Maritime Administration. (transportation Systems Center, Research and Special Programs Administration, Cambridge MA 02142~. Ponce, Paul V. 1990. An analysis of marine total losses worldwide and for selected flags. Marine Technology 27~2~:114-116. March.

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U.S. oceangoing vessels have half the crew size of 30 years ago, thanks to automation and mechanization in the shipping industry. But are reductions in crew size increasing the risk of vessel accidents? Crew Size and Maritime Safety explores how we can minimize risk without hindering technology, presenting the most thorough analysis available of key issues such as domestic versus foreign manning practices and safety performance; effect of crew size on crew fatigue, level of training, and ship maintenance; and modernizing the U.S. Coast Guard approach to crew size regulation.

The volume features a trend analysis of 20 years of maritime safety data, analyzing U.S. and international laws and treaties concerning ship manning and making recommendations for improvements. In addition, it includes a model for setting optimum crew levels, based on systems engineering and tested with actual ships.

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