[Case Study] CityCenter and Cosmopolitan Construction Projects, Las Vegas, Nevada: Lessons learned from the use of multiple sources and mixed methods in a safety needs assessment

Problem

The present study describes a response to eight tragic deaths over an eighteen month times span on a fast track construction project on the largest commercial development project in U.S. history.

Methods

Four versions of a survey were distributed to workers, foremen, superintendents, and senior management. In addition to standard Likert-scale safety climate scale items, an open-ended item was included at the end of the survey.

Results

Safety climate perceptions differed by job level. Specifically, management perceived a more positive safety climate as compared to workers. Content analysis of the open-ended item was used to identify important safety and health concerns which might have been overlooked with the qualitative portion of the survey.

Discussion

The surveys were conducted to understand workforce issues of concern with the aim of improving site safety conditions. Such efforts can require minimal investment of resources and time and result in critical feedback for developing interventions affecting organizational structure, management processes, and communication.

Summary

The most important lesson learned was that gauging differences in perception about site safety can provide critical feedback at all levels of a construction organization.

Impact on the Industry

Implementation of multi-level organizational perception surveys can identify major safety issues of concern. Feedback, if acted upon, can potentially result in fewer injuries and fatal events.     

Increasing self-awareness among older drivers: The role of self-screening

Introduction

Self-screening by older drivers has shown considerable promise for increasing self-awareness about functional abilities associated with safe driving. The purpose of this study was to improve upon existing self-screening instruments by focusing entirely on “health concerns” that affect driving - that is, the symptoms that people experience due to medical conditions and the medications used to treat them - rather than the medical conditions or medications themselves.

Method

A computer-based, easy-to-use self-screening instrument for older drivers was developed to provide individualized feedback intended to increase self-awareness about declines in driving-related abilities, as well as suggestions for behavioral changes or safety tips to maintain safe driving, further evaluation from a physician/health professional, and vehicle modifications to help compensate for driving-related declines.

Results

This paper describes the development of the self-screening instrument and summarizes findings relative to increasing self-awareness among older drivers. This research represents an important first step in improving self-awareness among older drivers through self-screening.     

Bio-optimization of the carbon-to-nitrogen ratio for efficient vermicomposting of chicken manure and waste paper using <Emphasis Type="Italic">Eisenia fetida</Emphasis>

The main objective of the present study was to determine the optimum C/N ratio for converting waste paper and chicken manure to nutrient-rich manure with minimum toxicity. Six treatments of C/N ratio 20, 30, 40, 50, 60, and 70 (T1, T2, T3, T4, T5, and T6, respectively) achieved by mixing chicken manure with shredded paper were used. The study involved a composting stage for 20 days followed by vermicomposting with Eisenia fetida for 7 weeks. The results revealed that 20 days of composting considerably degraded the organic waste mixtures from all treatments and a further 7 weeks of vermiculture significantly improved the bioconversion and nutrient value of all treatments. The C/N ratio of 40 (T3) resulted in the best quality vermicompost compared to the other treatments. Earthworm biomass was highest at T3 and T4 possibly due to a greater reduction of toxic substances in these waste mixtures. The total N, total P, and total K concentrations increased with time while total carbon, C/N ratio, electrical conductivity (EC), and heavy metal content gradually decreased with time during the vermicomposting process. Scanning electron microscopy (SEM) revealed the intrastructural degradation of the chicken manure and shredded paper matrix which confirmed the extent of biodegradation of treatment mixtures as result of the composting and vermicomposting processes. Phytotoxicity evaluation of final vermicomposts using tomato (Lycopersicon esculentum), radish (Raphanus sativus), carrot (Daucus carota), and onion (Allium cepa) as test crops showed the non-phytotoxicity of the vermicomposts to be in the order T3 > T4 > T2 > T1 > T5 > T6. Generally, the results indicated that the combination of composting and vermicomposting processes is a good strategy for the management of chicken manure/paper waste mixtures and that the ideal C/N ratio of the waste mixture is 40 (T3).     

Microscale air quality impacts of distributed power generation facilities

The electric system is experiencing rapid growth in the adoption of a mix of distributed renewable and fossil fuel sources, along with increasing amounts of off-grid generation. New operational regimes may have unforeseen consequences for air quality. A three-dimensional microscale chemical transport model (CTM) driven by an urban wind model was used to assess gaseous air pollutant and particulate matter (PM) impacts within ~10 km of fossil-fueled distributed power generation (DG) facilities during the early afternoon of a typical summer day in Houston, TX. Three types of DG scenarios were considered in the presence of motor vehicle emissions and a realistic urban canopy: (1) a 25-MW natural gas turbine operating at steady state in either simple cycle or combined heating and power (CHP) mode; (2) a 25-MW simple cycle gas turbine undergoing a cold startup with either moderate or enhanced formaldehyde emissions; and (3) a data center generating 10 MW of emergency power with either diesel or natural gas-fired backup generators (BUGs) without pollution controls. Simulations of criteria pollutants (NO₂, CO, O₃, PM) and the toxic pollutant, formaldehyde (HCHO), were conducted assuming a 2-hr operational time period. In all cases, NO_x titration dominated ozone production near the source. The turbine scenarios did not result in ambient concentration enhancements significantly exceeding 1 ppbv for gaseous pollutants or over 1 µg/m³ for PM after 2 hr of emission, assuming realistic plume rise. In the case of the datacenter with diesel BUGs, ambient NO₂ concentrations were enhanced by 10–50 ppbv within 2 km downwind of the source, while maximum PM impacts in the immediate vicinity of the datacenter were less than 5 µg/m³.

Implications: Plausible scenarios of distributed fossil generation consistent with the electricity grid’s transformation to a more flexible and modernized system suggest that a substantial amount of deployment would be required to significantly affect air quality on a localized scale. In particular, natural gas turbines typically used in distributed generation may have minor effects. Large banks of diesel backup generators such as those used by data centers, on the other hand, may require pollution controls or conversion to natural gas-fired reciprocal internal combustion engines to decrease nitrogen dioxide pollution.     

Blood on the coal: The effect of organizational size and differentiation on coal mine accidents

Introduction

Each year, there are at least 100,000,000 occupational accidents and 100,000 occupational deaths in the world. In the United States, one of the safest countries in the world in which to work, there were more than 5,400 workplace fatalities and 5.9 million workplace injuries in 2007. The cost to American industry and taxpayers is estimated to be at least $170 billion per year. Further, as illustrated by accidents such as Three Mile Island and Bhopal, industrial accidents potentially impact a much wider sphere than that of the injured worker and his or her employer. As the repercussions of organizational accidents reverberate through organizations and are felt from human resources to accounting, firms are beginning to incorporate messages of safety in their missions and strategies. As firms organize to achieve safer work environments, they are faced with decisions on how to structure their activities in terms of, among other things, size and differentiation.

Method

This paper explores the impact on accident rates of size and differentiation at the corporate and mine levels of mining companies in an effort to create a framework for thinking about organizational accidents from a structural perspective.

Results

The results suggest that larger mines are safer than smaller mines, and that mines with less task diversity are safer than mines with greater task diversity. The results also suggest that at the corporate level, task diversity decreases mine accidents. These results may help mining executives and engineers structure their corporate activities and individual mines more effectively to help reduce accidents.     

Pediatrician attitudes, knowledge, and practice behavior regarding teen driving safety

Problem

Each year about 4,000 teens ages 16-19 die on U.S. roads. Injury prevention counseling is recommended as a valuable and cost-effective part of routine health supervision. This study describes pediatrician knowledge and practice regarding teen driving safety.

Methods

A 31-item self-administered survey was mailed to pediatricians.

Results

160 of 392 pediatricians (41%) completed the survey. During a health supervision visit 93% of pediatricians reported discussing seat belt use, 89% impaired driving, 54% teen licensing laws, and 16% parent teen contract. Half reported having a teen in their practice killed in a crash.

Conclusions

A majority surveyed report discussing and counseling teens on first wave teen driver safety issues (seat belts, alcohol use), but most do not discuss graduated driver licensing laws or related issues. Impact on Industry: Broadly adopted, this inexpensive counseling approach, could lead to reductions in teen motorvehicle crash injuries.     

Injury severity related to overturn characteristics of tractors

Introduction

Early studies of injuries associated with overturns indicate that more fatalities occurred when a tractor overturned beyond 90° (continuous roll) relative to the impact plane. Recently, the principle of preventing continuous rolls has re-emerged for the protection of riding lawnmower operators.

Method

Related to tractors, a population-based study was conducted that compared the severity of fatal and nonfatal injuries between a 90° and continuous roll for tractors equipped with rollover protective structures (ROPS) and not equipped with a ROPS (non- ROPS). In 2002, the Kentucky Farm Tractor Overturn Survey was administered to an 8% random sample (6,063) of Kentucky farm operators. The farmers responded to questions that differentiated between the types of overturns and operator injury outcomes for ROPS-equipped and non-ROPS tractors during overturn events. Overturn characteristics were collected that included 90° to the side, beyond 90° to the side, and to the rear for both ROPS-equipped and non-ROPS tractors.

Results

Of the 541 overturns reported in this study, 535 (99%) of the respondents reported the most recent overturn characteristics of the tractor: 92 (17%) were ROPS-equipped and 443 (83%) were non-ROPS. For side overturns, 67% of the rolls occurred with ROPS-equipped tractors, and 54% occurred with non-ROPS tractors. The percentages of deaths related to rolls to the side for ROPS-equipped and non-ROPS tractors were, respectively, 1.6% and 3.7%. There was one (2%) deaths related to 90° rolls for ROPS-equipped tractors, whereas for continuous rolls there were 6.4% fatalities related to side overturns, 13% resulted in non-fatal injuries with an average of 1 day of hospitalization for ROPS-equipped tractors, and 39% resulted in non-fatal injuries with an average of 18 days of hospitalization for non-ROPS tractors. The results from this study indicated that a ROPS was more effective at stopping an overturn at 90° than no ROPS, with an associated reduction in the severity of injury in the event of a tractor overturn.     

Dissociation between driving performance and drivers' subjective estimates of performance and workload in dual-task conditions

Introduction

The current study measured how concurrent driving and in-vehicle activities of different levels of engagement varied in terms of performance and subjective estimates of demand and performance.

Method

In this test track study, 41 younger and older drivers completed a series of cognitive tasks while driving an instrumented vehicle. One task involved an engaging guessing game where drivers tried to guess the identity of an object. The other task involved a simple mental arithmetic task.

Results

We observed some dissociation between drivers' performance and their subjective reports. For instance, drivers tended to estimate their performance as better for the more engaging guessing task than the arithmetic task, though their performance was actually worse. At the same time, subjective estimates of workload across the two tasks did not vary in the dual-task condition even though they did in the single-task baseline conditions, suggesting that drivers failed to account for the added demands in dual-task situations.

Conclusions

We discuss the implications of these findings for driver safety.

Impact on Industry

Crashes due to distraction can carry tremendous costs for employers, in terms of injury, disability, and loss of potentially productive work years, whether these crashes occur on or off the job.     

Results from a national survey of Crown prosecutors and defense counsel on impaired driving in Canada: A “System Improvements” perspective

Introduction

This article summarizes the main findings from a study designed to examine the legal process in Canada as it applies to alcohol-impaired driving from the point of view of Crown prosecutors and defense counsel, and to identify evidentiary or procedural factors that may impact the legal process, the rights of the accused, and interactions of all parts in the legal process.

Method

The data in this study were collected by means of a survey that was mailed out to the population of Crown prosecutors and defense counsel in Canada. In total, 765 prosecutors and 270 defense lawyers or an estimated 33% of all Canadian prosecutors and 15% of defense lawyers completed and returned the questionnaire. The "systems improvement" paradigm was used to interpret the findings and draw conclusions. Such an approach acknowledges the importance of the context in which countermeasures are implemented and delivered and the structures or entities used to deliver countermeasures to a designated target group.

Results

Results on type of charges and breath alcohol concentration, caseload, case outcomes, case preparation time, conviction rate at trial and overall conviction rate, reasons for acquittals and time to resolve cases are described.

Discussion

The findings from this national survey suggest that there are important challenges within the criminal justice system that impede the effective and efficient processing of impaired driving cases. Some of these challenges occur as a function of practices and policies, while others occur as a function of legislation.

Impact on industry

This study illustrates that a "system improvements" approach that acknowledges the importance of all elements of the criminal justice system and the interaction between those elements, can be beneficial in overcoming the alcohol-impaired driving problem.