Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.

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The effectiveness of speed limits has been the subject of considerable debate over the years. In most cases in the past, speed limits have been changed because of a single factor (e. g. improving the safety of road traffic or saving energy). In this thesis an attempt has been made to evaluate the consequences of changing a speed limit using cost-benefit analysis which formed the principle objective of this study. The scope was confined to motorways and similar high-quality roads operating under free-flow traffic conditions where speed limits were believed to be most effective. To achieve the main goal, the effect of the speed limit on the mean speed of traffic was investigated which was the second objective of the study. The third objective was to find the effect of the speed of traffic, and especially the mean speed of traffic, on the frequency and severity of personal injury accidents. There was a need to investigate these two relationships as the literature was not consistent on these relationships. A hypothesis was proposed to achieve the second objective. This was tested by defining criteria that had to be met for each of the data collection sites and measuring the speed of vehicles. There were II sites in Tyne & Wear, England and 14 sites in the State of Bahrain. A statistical analysis was applied to the data collected. It was found, from both sets of data, that speed limits had a positive effect on the mean speed and the eighty-fifth percentile speed of traffic. Linear and non-linear (multiplicative) models were developed for each set of data. In addition to the speed limit, the trip length and the length of the section were shown to affect significantly the mean speed of traffic. The amount of change in the mean speed of traffic varied between the models tested but, generally, for every 4 to 5 km/h change in the speed limit the mean speed of traffic changed by, about, I km/h. In a similar way, a hypothesis was proposed to pursue the third objective. Criteria were established for the selection of suitable data collection sites and for the types of accidents. 9 sites were selected in Tyne & Wear and 10 sites in the State of Bahrain. Data was drawn from a5 year set of accident records in Tyne and Wear and a four year set in the State of Bahrain. A statistical analysis was applied to the data. The set of data from Tyne & Wear revealed no significant relationship between the mean speed of traffic and the frequency of accidents but the speed differentials affected the frequency of the personal injury accidents. The data from Bahrain showed that both the mean speed of traffic and the speed differentials of vehicles affected the frequency of the personal injury accidents. No significant relationships were found between the speed of vehicles and the severity of the personal injury accidents. The principle objective of the study was achieved by applying cost-benefit analysis to the consequences of changing the speed limit for a hypothetical typical section of road. The components of cost were the cost of travel-time, the vehicle operating cost, and the cost of accidents. No monetary values were assigned to the environmental effects so it was not possible to include them in the cost-benefit analysis but they were acknowledged. Any changes in air pollution and noise annoyance due to a change in the mean speed of traffic following a change in a speed limit were likely to be small and were not considered in the study. The significance of the uncertainty in the frequency and severity of personal injury accidents in relation to the mean speed of traffic was studied using 'break-even analysis'. Generally, it was believed that lowering the speed limit on motorways and similar high-quality roads would produce negative benefits, even if the frequency and severity of personal injury accidents decreasedw ithin expectedr anges. Increasing the speed limits would produce positive economic benefits but the conclusion was less firm than the previous case. Sensitivity analysis was applied to the variables used in the cost-benefit analysis. It was found that the net benefits were most sensitive to the estimation of the effect of the speed limits on the mean speed of traffic, the initial mean speed of traffic in the base year of the assessment, the travel-time cost, the changes in the frequency of the personal injury accidents, and changes in the number of fatal injury casualties per average personal injury accident as the speed limit varied (i. e. in descending order for most speed limits). The ranking of these variables differed as the speed limit was changed.

Thesis (doctoral)--University of Uppsala, 1984. / Includes bibliographical references (p. 28-33).

Afhandling--Aarhus University. / Bibliography: p. 302-310.

The conclusions reached in this study lead to some rather perplexing implications. The first relates to the whole matter of measuring human perceptions through the use of a questionnaire. It is possible that the individuals sampled in this study did not give completely honest answers to every question. If, in fact, this did occur, the reason may be that each of the individuals has had a considerable amount of safety related training throughout his federal service career as a part of his skill training. Thus, he may give the "proper" answer even though he may not implement the safety principle. Certainly, the questionnaire used in this study is not completely without fault. One can never be sure, for example, that rating scales are sufficiently balanced or that the questions are completely understood by the respondents. Thus, in any study employing questionnaires, there is always some error built in. However, the questionnaire was the same for all respondents, therefore, the error can be assumed to be equally distributed throughout the sample group. A second implication is that the responses to a number of the questions contained a sufficiently large number of U answers that analyzing A and Not-A instead of D and Not-D would have had a significant affect on the outcome of the analysis. While A responses outnumbered Not-A responses by 319 to 289 (52.5 to 47.5 per cent, respectively) this difference is not significant. However, the outcome of the analysis of a number of questions would have changed and it may have been possible to make a stronger case for accepting Kerr's proposal if the U responses had been considered as Not-A responses. A third implication deals with the matter of the interaction of factors in influencing the perceptions supervisors hold about safety. In this study, age and supervisory level were treated separately. However, it is possible that a thorough analysis of the interaction of these two variables taken from a larger sample size could prove significant. Unfortunately, in this study the number of respondents in high age, lower level and low age, higher level categories was too small to perform statistically significant analysis. A final implication deals with difference within populations in regard to skill specialty. It is possible, for example, that vehicle mechanics hold differing perceptions of appropriate safety behavior than do aircraft mechanics. It would be interesting, and hopefully significant, to determine if differences in skill specialties have any effect on the perceptions of appropriate safety behavior. / Master of Science

The Health and Safety Executive estimated the annual cost to British employers and other duty holders failing to comply with health and safety requirements to be up to £18 billion. It is estimated that the construction industry contributed £2billion of these appalling statistics. To date, health and safety management is still perceived as being costly and counterproductive in the construction industry. This research investigated the net benefit of accident prevention and explored the relationship between preventative costs and these benefits, with a view to drawing attention to the economic consequences of effective/ineffective management of health and safety by contractors in the UK construction industry. The need to investigate the cost of accident prevention in relation to overall benefits of accident prevention is therefore deemed necessary. A quantitative research methodology was employed in investigating these costs and benefits within the UK construction industry. From the ratio analysis small contractors spend relatively higher proportions of their turnover in total on accident prevention than medium and large contractors, and medium contractors spend a higher proportion of their turnover in total on accident prevention than large contractors. The results also show that medium and small contractors gain relatively higher proportions of their turnover in total as benefits of accident prevention than large contractors. The benefits of accident prevention far outweigh the costs of accident prevention by a ratio approximately 3:1. The relationships between these costs and benefits were examined. The costs of accident prevention were found to be positively and significantly (P < 0.005) associated with benefits of accident prevention. These associations were modelled using simple linear regression, and from these models it can be inferred from the results that the more contractors spend on accident prevention the more they derive benefits of accident prevention, which would improve health and safety performance on construction sites. ii The developed model was subsequently validated using experts and practitioners opinion from the UK construction industry. This developed model should provide good guidance to assist contractors in developing effective and efficient health and safety management for UK construction industry.

Waka have a special place in the heart of many Maaori. The waka that brought the ancestors of the Maaori to Aotearoa and Te Waipounamu are valued symbols of identity, both culturally and metaphorically. With the effects of colonisation the use of waka as a means of transport disappeared leaving it to re-emerge in the 20th century as a symbol of the revitalisation of Maaori society. Through the construction of waka-taua, ocean going waka and the emergence of waka-ama as a sport, Maaori have endeavoured to reclaim their association to the seas and waterways of New Zealand. This research is a case study of Tupuwae, a kaupapa Maaori injury prevention project using traditional Maaori concepts regarding waka and applying it to a contemporary context. Tapuwae have used this attachment of Maaori to different forms of waka to associate the message of not drinking and driving using purpose-built waka-ama in the southern part of Te Waipounamu. This research identifies some of the wider outcomes that come from a kaupapa Maaori project, but, more importantly it identifies some of the processes that are important in implementing such a project by Maaori living in Otago, outside their tribal boundaries. This research also raises questions about the theoretical underpinnings of kaupapa Maaori theory and argues that there are two threads to this approach, one from a critical theory informed approach and the other from a native theory approach. Key words:Waka, Community Action, Community Development, Kaupapa Maaori, Maaori Development, Maaori Advancement, Native Theory.