Chemical plant innovative safety investments decision-support methodology

Introduction

This article examines the extent to which investing in safety during the creation of a new chemical installation proves profitable.

Method

The authors propose a management supporting cost-benefit model that identifies and evaluates investments in safety within a chemical company. This innovative model differentiates between serious accidents and less serious accidents, thus providing an authentic image of prevention-related costs and benefits. In classic cost-benefit analyses, which do not make such differentiations, only a rudimentary image of potential profitability resulting from investments in safety is obtained.

Results

The resulting management conclusions that can be drawn from such classical analyses are of a very limited nature. The proposed model, however, is applied to a real case study and the proposed investments in safety at an appointed chemical installation are weighed against the estimated hypothetical benefits resulting from the preventive measures to be installed at the installation.

Conclusion

In the case-study carried out in question, it would appear that the proposed prevention investments are justified.

Impact on industry

Such an economic exercise may be very important to chemical corporations trying to (further) improve their safety investments.     

The use of proactive risk management to reduce emergency service vehicle crashes among firefighters

IntroductionEmergency service vehicle crashes (ESVCs), including rollovers and collisions with other vehicles and fixed objects, are a leading cause of death among U.S. firefighters. Risk management (RM) is a proactive intervention to identifying and mitigating occupational risks and hazards. The goal of this study was to assess the effect of RM in reducing ESVCs. Methods: Three fire departments (A, B and C), representing urban and suburban geographies, and serving medium to large populations, participated in facilitated RM programs to reduce their ESVCs. Interventions were chosen by each department to address their department-specific circumstances and highest risks. Monthly crash rates per 10,000 calls were calculated for each department an average of 28 months before and 23 months after the start of the RM programs. Interrupted time series analysis was used to assess the effect of the RM programs on monthly crash rates. Poisson regression was used to estimate the number of crashes avoided. Economic data from Department A were analyzed to estimate cost savings. Results: Department A had a 15.4% (P = 0.30) reduction in the overall monthly crash rate immediately post-RM and a 1% (P = 0.18) decline per month thereafter. The estimated two-year average cost savings due to 167 crashes avoided was $253,100 (95%CI= $192,355 – $313,885). Department B had a 9.7% (P = 0.70) increase in the overall monthly crash rate immediately post-RM and showed no significant changes in their monthly crash rate. Department C had a 28.4% (P = 0.001) reduction in overall monthly crash rate immediately post-RM and a 1.2% (P = 0.09) increase per month thereafter, with an estimated 122 crashes avoided. Conclusions: RM programs have the potential to reduce ESVCs in the fire service and their associated costs; results may vary based on the interventions chosen and how they are implemented. Practical applications: Risk management may be an effective and broadly implemented intervention to reduce ESVCs in the US fire service.     

Disparities in the prevalence of smoke alarms in U.S. households: Conclusions drawn from published case studies

Introduction

Deaths from fires and burns are a leading cause of fatal home injury in the United States. Smoke alarms are one of the most effective interventions to prevent residential fire deaths. Nationwide, more than 95% of homes are estimated to have at least one smoke alarm. There is evidence that homes at highest risk of fire deaths lag behind national averages in smoke alarm use and maintenance.

Method

We compiled a comprehensive list of published studies that focus on smoke alarm prevalence in high-risk homes. Our findings show that there are substantial gaps in both smoke alarm presence and functional status between high-risk homes and national average estimates.

Conclusions

To save more lives, improved efforts are needed to reduce the disparity in smoke alarm prevalence and functional use in the United States.     

The role of local communities in chemical accident prevention and preparedness

Since the adoption of community right-to-know programs in the US there has been an increase in the number of groups known as local emergency planning committees. These committees have matured in focus over the intervening years since the Bhopal incident and even more so since the events of September 11, 2001. There is a strong recognition that local communities working very closely with chemical handling facilities in their areas can directly and meaningfully reduce the threat of a chemical release incident, regardless of cause. Likewise, through similar means they can better prepare themselves to respond should an incident occur. Especially as regards modern concepts of process chemical safety and facility security, local communities can be of great assistance to smaller facilities that do not otherwise necessarily have the resources to accomplish these tasks. As the vulnerabilities of a facility to accident or intentional act, the impacts of these events and the ability of communities to react are all a function of local conditions, it is clear that these local efforts can be more meaningful than large-scale national efforts. While national legislation is certainly helpful to the process of bringing people together, it is the local relationships that produce results.     

劳动安全卫生费用模型

劳动安全卫生费用模型 (图 2 )反映了预防投资、事故费用、总费用与企业安全水平之间的关系。最小值 M点是一个正常的企业应当追求的状态 ,该状态使企业在总投资最小的情况下 ,达到较好的安全水平。图 4是因未感觉间接费用而造成对费用模型的扭曲。图 5、图 6是企业极度忽视安全卫生而又得不到惩戒时使费用模型受到的扭曲。扭曲的费用模型使企业预防投资的经济动力减弱或失去。蔑视劳动者生命价值的结果最终也会损害企业经济的发展。对所有扭曲的情况 ,既需要社会、法律的约束 ,也需要安全经济学的引导。     

Safety and economic impacts of photo radar program

OBJECTIVE: Unsafe speed is one of the major traffic safety challenges facing motorized nations. In 2003, unsafe speed contributed to 31 percent of all fatal collisions, causing a loss of 13,380 lives in the United States alone. The economic impact of speeding is tremendous. According to NHTSA, the cost of unsafe speed related collisions to the American society exceeds 40 billion US dollars per year. In response, automated photo radar speed enforcement programs have been implemented in many countries. This study assesses the economic impacts of a large-scale photo radar program in British Columbia. The knowledge generated from this study could inform policy makers and project managers in making informed decisions with regard to this highly effective and efficient, yet very controversial program. METHODS: This study establishes speed and safety effects of photo radar programs by summarizing two physical impact investigations in British Columbia. It then conducts a cost-benefit analysis to assess the program's economic impacts. The cost-benefit analysis takes into account both societal and funding agency's perspectives. It includes a comprehensive account of major impacts. It uses willingness to pay principle to value human lives saved and injuries avoided. It incorporates an extended sensitivity analysis to quantify the robustness of base case conclusions. RESULTS: The study reveals an annual net benefit of approximately 114 million in year 2001 Canadian dollars to British Columbians. The study also finds a net annual saving of over 38 million Canadian dollars for the Insurance Corporation of British Columbia (ICBC) that funded the program. These results are robust under almost all alternative scenarios tested. The only circumstance under which the net benefit of the program turns negative is when the real safety effects were one standard deviation below the estimated values, which is possible but highly unlikely. CONCLUSION: Automated photo radar traffic safety enforcement can be an effective and efficient means to manage traffic speed, reduce collisions and injuries, and combat the huge resulting economic burden to society. The cost-effectiveness of the program takes on special meaning and urgency when considering the present and future government funding constraints. The application of the program, however, should be planned and implemented with caution. Every effort should be made to focus on and to promote the program on safety improvement grounds. The program can be easily terminated because of political considerations, if the public perceives it as a cash cow to enhance government revenue.     

Interlocks for first offenders: effective?

OBJECTIVE: Vehicle interlocks have been shown to effectively reduce the recidivism of multiple driving-while-impaired (DWI) offenders; however, the evidence for their effectiveness with first offenders has been mixed. Two Canadian studies found that the installation of an interlock reduced first DWI recidivism, but U.S. studies in West Virginia and California failed to find a significant reduction in recidivism for first DWI offenders in interlock programs. The objective of this study was to determine the extent to which such devices were effective with first offenders in New Mexico. METHODS: This study compared 1,461 first offenders, who installed interlocks in New Mexico between January 1, 2003, and December 1, 2005, with 17,562 first offenders convicted during the same period who did not install the units. Cox multivariate proportional hazards regression (CMVPHR) was used to compare recidivism rates during three periods: while the interlock was on the vehicles of offenders who installed them, after those offenders removed the units until the end of the study period (approximately 2 years), and for the combined period (both while the interlock was installed and after it was removed). RESULTS: While the device was on the vehicles of the interlock group, their recidivism rate, 2.6% per year of exposure, was significantly less than the 7.1% per year rate of the comparison group (CMVPHR hazard ratio = 0.39, p < 0.0001). After the device was removed, the annualized recidivism rate of the interlock group increased to 4.9% per year of exposure, which was less than the 6.7% rate of the comparison group, but the hazard ratio was not statistically significant (CMVPHR hazard ratio = 0.82, p = 0.16). When the combined periods (interlock on and off) were considered, the interlock group had a recidivism rate of 3.9% per year, which again was significantly lower than the 6.8% rate for the comparison group (CMVPHR hazard ratio = 0.61, p < 0.0001). CONCLUSION: The study provides evidence that interlocks are as effective with first offenders (approximately 60% reduction in recidivism when on the vehicle) as they are for multiple offenders. In addition, the benefits of requiring an interlock for first offenders exceed the costs by a factor of three.     

火灾自动报警系统可靠性研究

火灾自动报警系统主要包括火灾探测器、火灾报警控制器、减灾装置和灭火装置4部分,从这4部分分析了其工作原理。在此基础上,着重分析了误报、漏报概率较高的火灾探测系统(包括火灾探测器和火灾报警控制器)在使用过程中可能出现的失效状态。其失效的根本原因是在探测器的设计、选型与安装中出现的问题以及各类控制器和控制软件出现的问题。火灾自动报警系统在设计、安装和使用过程中出现的一些问题可能导致整个系统失效,主要包括硬件故障、系统失误和管理缺陷3类。因此,从火灾自动报警系统设计、软硬件产品质量、选型与安装及维护保养等方面给出了提高火灾自动报警系统可靠性的措施。最后应用系统安全及可靠性理论建立了包括电源系统、触发装置、报警控制装置和警报装置4个指标的火灾自动报警系统可靠度计算模型。     

Safety effectiveness and crash cost benefit of red light cameras in Missouri

Objective: Red light cameras (RLCs) have generated heated discussions over issues of safety effectiveness, revenue generation, and procedural due process. This study focuses on the safety evaluation of RLCs in Missouri, including the economic valuation of safety benefits. The publication of the national Highway Safety Manual (HSM; American Association of State Highway and Transportation Officials) in 2010 produced statistical safety models for intersections and spurred the calibration of these models to local conditions.

Methods: This study adds to existing knowledge by applying the latest statistical methodology presented in the HSM and more current data. Driver behavior constantly changes due in part to driving conditions and the use of technology. The safety and economic benefit evaluation was performed using the empirical Bayes method, which accounts for regression to the mean bias. For the economic benefit evaluation, the KABCO crash severity scale and crash cost estimates were used. A total of 24 4-leg urban intersections were randomly selected from a master list of RLCs in Missouri from 2006 to 2011. Additionally, 35 comparable nontreated intersections were selected for the analysis.

Results and Conclusions: The implementation of RLCs reduced overall angle crashes by 11.6%, whereas rear-end crashes increased by 16.5%. The net economic crash cost benefit of the implementation of RLCs was $35,269 per site per year in 2001 dollars (approximately $47,000 in 2015 dollars). Thus, RLCs produced a sizable net positive safety benefit that is consistent with previous statistical studies.     

Vigilance monitoring for operator safety: A simulation study on highway driving

INTRODUCTION: Alertness of individuals operating vehicles, aircrafts, and machinery is a pre-requisite for safety of the individual and for avoiding economic losses. In this paper, we present a new technique for determining the alertness level of the operator and elaborate the methodology for the specific case of highway driving METHOD: Our hypothesis is that the time derivative of force exerted by the driver at the vehicle-human interfaces can be used to construct a signature of individual driving styles and to discern different levels of alertness RESULTS: In this study, we present experimental results corroborating this hypothesis and introduce a parameter, 'spikiness index,' for the time series data of the force derivative to quantify driver alertness IMPACT ON INDUSTRY: The low cost, ruggedness, and low-volume data processing requirements of the proposed technique give it a competitive edge over existing predominantly image processing based vigilance monitoring systems.     

Improvement of the performance of animal crossing warning signs

Introduction: Animal–vehicle collisions (AVCs) can result in serious injury and death to drivers, animals' death, and significant economic costs. However, the cost effectiveness of the majority of AVC mitigation measures is a significant issue. Method: A mobile-based data collection effort was deployed to measure signs under the Utah Department of Transportation's (UDOT) jurisdiction. The crash data were obtained from the UDOT risk management database. ArcGIS was employed to link these two data sets and extract animal-related crashes and signs. An algorithm was developed to process the data and identify AVCs that occurred within sign recognition distance. Kernel density estimation (KDE) technique was applied to identify potential crash hotspots. Results: Only 2% of AVCs occurred within the recognition distance of animal crossing signs. Almost 58% of animal-related crashes took place on the Interstate and U.S. highways, wherein only 30% of animal crossing signs were installed. State routes with a higher average number of signs experienced a lower number of AVCs per mile. The differences between AVCs that occurred within versus outside of sign recognition distance were not statistically significant regarding crash severity, time of crash, weather condition, driver age, vehicle speed, and type of animal. It is more likely that drivers become accustomed to deer crossing signs than cow signs. Conclusions: Based on the historical crash data and landscape structure, with attention given to the low cost safety improvement methods, a combination of different types of AVC mitigation measures can be developed to reduce the number of animal-related crashes. After an in-depth analysis of AVC data, warning traffic signs, coupled with other low cost mitigation countermeasures can be successfully placed in areas with higher priority or in critical areas. Practical applications: The findings of this study assist transportation agencies in developing more efficient mitigation measures against AVCs.     

Mandating interlocks for fully revoked offenders: the New Mexico experience

OBJECTIVE: In New Mexico, between July 1999 and December 2002, the installation of an ignition interlock was an optional judicial sanction for second and third driving-while-impaired (DWI) offenders. This is a study of the recidivism of 437 offenders who were convicted and installed interlocks for an average of 322 days during that period. METHODS: The comparison group was a stratified random sample (N = 12,554) of the 20,949 offenders who were convicted during the same period but did not install interlocks. DWI arrest and conviction data for all study participants were received from the Motor Vehicle Department's Citation Tracking System. RESULTS: Only 11 (2.5%) of the interlock offender group were rearrested for DWI while interlocks were installed, whereas 1,017 (8.1%) of the comparison group were rearrested during an equivalent 322-day period. Survival graphs and Cox proportional hazard regression analyses were used to compare the interlock and noninterlock groups during installation, after installation, and for the entire period up to December 2004. Results indicate a reduction in recidivism of 65% during installation. After removal, there was no significant difference in recidivism rates in a 3-year follow-up period. Following all offenders for 4 years, including both the period while the interlock was installed and the period after its removal, indicates that the difference in recidivism achieved during installation, though not increased, is maintained, so at the end of 4 years, interlock users still have lower total recidivism than nonusers. CONCLUSIONS: The magnitude of interlock effectiveness reported here is similar to those in other published studies with comparable samples.     

A process mapping model for calculating indirect costs of workplace accidents

This article follows an earlier one in which four criteria and four bases for the development of an indirect-cost calculation model adapted to the accuracy requirements and time constraints of workplace decision-makers were established. A two-level model for calculating indirect costs using process mapping of the organizational response to a workplace accident is presented. The model is based on data collected in interviews with those employees in charge of occupational health and safety in 10 companies of various sizes in different industry sectors. This model is the first to use process mapping to establish the indirect costs of workplace accidents. The approach allows easy identification of the duration and frequency of actions taken by stakeholders when a workplace accident occurs, facilitates the collection of the information needed to calculate indirect costs and yields a usable, precise result. A simple graphic representation of an organization's accident processes helps the user understand each accident's cost components, allowing the identification and reduction of inefficiencies in the overall process. Impact on Industry: By facilitating data collection and shortening the time needed to assess indirect costs of workplace accidents, this indirect cost calculation tool is better suited for workplace use than those currently available.     

Reduced frequency and severity of residential fires following delivery of fire prevention education by on-duty fire fighters: cluster randomized controlled study

IntroductionIn 2008, Surrey Fire Services, British Columbia, commenced a firefighter-delivered, door-to-door fire-prevention education and smoke alarm examination/installation initiative with the intention of reducing the frequency and severity of residential structure fires in the City of Surrey.MethodHigh-risk zones within the city were identified and 18,473 home visits were undertaken across seven temporal delivery cohorts (13.8% of non-apartment dwellings in the city). The frequency and severity of fires pre- and post- the home visit intervention was examined in comparison to randomized high-risk cluster controls.ResultsOverall, the frequency of fires was found to have reduced in the city overall, however, the reduction in the intervention cohorts was significantly larger than for controls. Furthermore, when fires did occur within the intervention cohorts, smoke detectors were activated more frequently and the fires were confined to the object of origin more often post-home visits. No equivalent pattern was observed for the cluster control.Impact on IndustryOn-duty fire fighters can reduce the frequency and severity of residential fires through targeted, door-to-door distribution of fire prevention education in high-risk areas.     

基于贝叶斯估计的多探测器火警判定方法研究*

为应对感烟探测器的大量误报对消防应急响应带来的挑战,考虑目前以感烟探测器为主的火警设施误报率高且短期内难以全部更换的特点,提出基于贝叶斯估计的多探测器火警判定方法,通过多个探测器的报警时间间隔计算火源位置的后验概率分布,并提出火警真实度概念,为火警判定提供依据。结果表明:使用多探测器耦合模型时每增加1个探测器可将误报率降低约4个数量级,该方法在探测器正常、部分失效、误报的情景下均能有效判别火警。     

Forecasting turbine problems by means of the state space framework

A forecasting system is set up to improve the diagnosis in a Condition Monitoring Programme of a critical turbine placed at an industrial plant. The system is based on a statistical model in a State Space framework, such that the local mean level of the vibration state of the equipment is estimated directly from the data, based on a continuous-time set up. This model is combined with a cost model in Conditioned Monitoring, by which the time of preventive replacement is produced when the minimum of the expected cost per unit of time is reached into the future. Such measure is a combination of the costs of failure, the costs of a preventive replacement and the probabilities of reaching the alarm levels fixed by some criteria. The system is estimated by Maximum Likelihood and thoroughly tested on the equipment. The main tests relate to statistical properties of the model residuals and a comprehensive comparison with an alternative system, namely a linear trend regression model in continuous time. The system produced a reasonable forecasting performance and sensible time of preventive replacement prediction and outperformed the alternative forecasting system.     

Lagging or leading? Exploring the temporal relationship among lagging indicators in mining establishments 2006–2017

Problem: Safety management literature generally categorizes key performance indicators (KPIs) as either leading or lagging. Traditional lagging indicators are measures related to negative safety incidents, such as injuries, while leading indicators are used to predict (and therefore can be used to prevent) the likelihood of future negative safety incidents. Recent theory suggests that traditional lagging indicators also possess characteristics of leading indicators, and vice versa, however empirical evidence is limited. Method: The current research investigated the temporal relationships among establishment-level injuries, near misses, and fatal events using injury and employment data from a sample of 24,910 mining establishments over a 12-year period. Results: While controlling for employee hours worked, establishment-level reported injuries and near misses were associated with of future fatal events across the sample of mines and over the time period studied. Fatal events were also associated with increases in future reported near misses, providing evidence of a cyclic relationship between them. Discussion: These findings challenge the strict categorization of injuries, near misses, and fatal events as lagging indicators. Practical applications: Understanding the KPIs that should be used to manage organizational safety, and how they can be used, is of critical practical importance. The results of the current study suggest that, depending on several considerations, metrics tied to negative safety incidents may be used to anticipate, and possibly prevent, future negative safety events.     

Railroad injury: Causes, costs, and comparisons with other transport modes

Safety regulators in the railroad industry need comprehensive injury costs by cause, and cost comparisons to other modes of transport to gain policy insights. This study links case-level data from the Federal Railroad Administration to monetary costs and consequences of specific injuries. Lost quality of life was estimated from physicians' ratings of injury impairment and the value of fatal risk reduction. Railroad injuries and illnesses cause an average of $3 billion in fatality costs and $650 million in nonfatal incident costs annually. Impacts at rail-highway crossings impose three times as much cost as the next highest cause. Commercial air travel is the safest per passenger mile. Trains, second lowest, have injury costs six times higher, but only one-fifth as high as cars. The relative safety of trains and airplanes in transport means highway modes enjoy implicit price subsidies. Better injury cost recovery through taxation or insurance would make the subsidies explicit. More informed modal choices and thus enhanced economic efficiency would result.     

Application of machine learning technique for optimizing roadside design to decrease barrier crash costs,a quantile regression model approach

Introduction: In-transport vehicles often leave the travel lane and encroach onto natural objects on the roadsides. These types of crashes are called run-off the road crashes (ROR). Such crashes accounts for a significant proportion of fatalities and severe crashes. Roadside barrier installation would be warranted if they could reduce the severity of these types of crashes. However, roadside barriers still account for a significant proportion of severe crashes in Wyoming. The impact of the crash severity would be higher if barriers are poorly designed, which could result in override or underride barrier crashes. Several studies have been conducted to identify optimum values of barrier height. However, limited studies have investigated the monetary benefit associated with adjusting the barrier heights to the optimal values. In addition, few studies have been conducted to model barrier crash cost. This is because the crash cost is a heavily skewed distribution, and well-known distributions such as linear or poison models are incapable of capturing the distribution. A semi-parametric distribution such as asymmetric Laplace distribution can be used to account for this type of sparse distribution. Method: Interaction between different predictors were considered in the analysis. Also, to account for exposure effects across various barriers, barrier lengths and traffic volumes were incorporated in the models. This study is conducted by using a novel machine-learning-based cost-benefit optimization to provide an efficient guideline for decision makers. This method was used for predicting barrier crash costs without barrier enhancement. Subsequently the benefit was obtained by optimizing traffic barrier height and recalculating the benefit and cost. The trained model was used for crash cost prediction on barriers with and without crashes. Results: The results of optimization clearly demonstrated the benefit of optimizing the heights of road barriers around the state. Practical Applications: The findings can be utilized by the Wyoming Department of Transportation (WYDOT) to determine the heights of which barriers should be optimized first. Other states can follow the procedure described in this paper to upgrade their roadside barriers.     

Benefit–cost analysis of lane departure warning and roll stability control in commercial vehicles

Introduction: This paper presents the cost benefits of two different onboard safety systems (OSS) installed on trucks as they operated during normal revenue deliveries. Using a formal economic analysis approach, the study quantified the costs and benefits associated with lane departure warning (LDW) systems and roll stability control (RSC) systems. Methods: The study used data collected from participating carriers (many of these crashes were not reported to state or Federal agencies), and the research team also reviewed each crash file to determine if the specific OSS would have mitigated or prevented the crash. The deployment of each OSS was anticipated to increase the safety of all road users, but impact different sectors of society in different ways. Benefits that were inherent in each group (e.g., industry, society) were considered, and different benefit–cost analyses (BCAs) were performed. Results: This paper presents two BCAs: a BCA focused on the costs and benefits in the carrier industry by implementing each OSS, and a BCA that measured the societal benefits of each OSS. In addition, a BCA for a theoretical mandatory deployment option for each OSS is presented. Conclusions: BCA results for LDW and RSC clearly showed their benefits outweighed their costs for the carrier and society. Practical applications: Cost information is a crucial factor in purchasing decisions in carriers; similarly, regulators must consider the cost burden prior to mandating technologies. The results in this study provide carrier decision makers and regulators with information necessary to make an informed decision regarding RSC and LDW.