Perceptions of implied hazard for visual and auditory alerting signals

Visual and auditory alerts are increasingly important and have many applications, particularly in the presentation of hazard information in transportation and many industrial systems. This paper is concerned with the factors that govern the relative effectiveness of alerting signals involving various combinations of visual and auditory signals. The visual variables were colour, flash rate, and flash mode, combined with or without an auditory alarm. It was found that the subjects associated different levels of hazard with different alerting light colours, flash rates, flashing modes, and with combinations of auditory and visual alerts. A red flashing light was perceived as the most effective hazard warning colour, with yellow and blue warning lights indicative of less hazardous situations. The faster the flash rate, the greater is the hazard perceived. A flash rate of 60 fpm (flashes per minute) was not as effective as the rates of 180 and 240 fpm, and 240 fpm was the most effective. This implies that hazard warning signal should flash at well above 60 fpm. Having a breakup in the flashing pattern so as to provide a double or triple flash mode also increases the effectiveness of the signal. There were significant interactions between the alert variables used. The difference in perceived hazard levels for the colours blue and yellow were statistically non significant, but blue was more effective in conveying hazard message than yellow at the high flash rates. When accompanied with auditory alarms, blue and yellow were perceived to convey the same perception level of hazard as red without auditory alarms. The effect of colour on perceived hazard was also found to vary with flash mode. As compared to either visual signal alone or a visual signal with other types of acoustic alarms, a siren type of auditory alarm was found more effective for eliciting perception of hazards. There was evidence that presenting alerting signal in triple-flash mode and at high flash rate could be annoying and might not help improving hazard awareness.     

Field effectiveness evaluation of advanced driver assistance systems

Abstract

Objective: Advanced driver assistance systems (ADAS) are a class of vehicle technologies designed to increase safety by providing drivers with timely warnings and autonomously intervening to avoid hazardous situations. Though laboratory testing suggests that ADAS technologies will greatly impact crash involvement rates, real-world evidence that characterizes their effectiveness is still limited. This study evaluates and quantifies the association of ADAS technologies with the likelihood of a moderate or severe crash for new-model BMWs in the United States.

Methods: Vehicle ADAS option information for the cohort of model year 2014 and later BMW passenger vehicles sold after January 1, 2014 (n?=?1,063,503), was coded using VIN-identified options data. ADAS technologies of interest include frontal collision warning with autonomous emergency braking, lane departure warning, and blind spot detection. BMW Automated Crash Notification system data (from January 2014 to November 2017) were merged with vehicle data by VIN to identify crashed vehicles (n?=?15,507), including date, crash severity (delta V), and area of impact. Using Cox proportional hazards regression modeling, the study calculates the adjusted hazard ratio for crashing among BMW passenger vehicles with versus without ADAS technologies. The adjusted percentage reduction in moderate and severe crashes associated with ADAS is interpreted as one minus the hazard ratio.

Results: Vehicles equipped with both autonomous emergency braking and lane departure warning were 23% less likely to crash than those not equipped (hazard ratio [HR]?=?0.77; 95% confidence interval [CI], 0.73–0.81), controlling for model year, vehicle size and body type. Autonomous emergency braking and lane departure warning generally occur together, making it difficult to tease apart their individual effects. Blind spot detection was associated with a 14% reduction in crashes after controlling for the presence of autonomous emergency braking and lane departure warning (HR =0.86; 95% CI, 0.744–0.99). Differences were observed by vehicle type and crash type. The combined effect of autonomous emergency braking and lane departure warning was greater in newer model vehicles: Equipped vehicles were 13% less likely to crash (HR =0.87; 95% CI, 0.79–0.95) among 2014 model year vehicles versus 34% less likely to crash (HR =0.66; 95% CI, 0.57–0.77) among 2017 model year vehicles.

Conclusion: This robust cohort study contributes to the growing evidence on the effectiveness of ADAS technologies.     

Explicitness of consequence information in warnings

Four experiments were carried out to assess effects of product warning explicitness on purchase preferences and caution in use. Explicitness was defined as the specificity or detail with which potential injury consequences were described. All experiments employed a paradigm in which warnings varying in explicitness were described for familiar products. Subjects rated various perceptions of the products, purchase preferences, and intent to act cautiously in using the product. Results indicated that more explicit warnings were associated with greater levels of perceived dangerousness, hazard understanding, injury severity, and manufacturers' concern. While explicit warnings were also associated with an increased intent to act cautiously in using products, no clear relationship was found between explicitness and purchase preferences. It is recommended that product warnings should be explicit regarding injury consequences, especially where injuries may be severe. Given such information, product users, particularly those less familiar with a product, are more likely to exercise greater caution during use. Further, manufacturers' concern that explicit warnings may negatively impact sales appears to be unwarranted.     

Comprehension and memory for warning symbols: age-related differences and impact of training

Problem: Prior research indicates that many warning symbols are poorly understood, particularly by the elderly. Method: The effectiveness of three different training conditions to improve comprehension and memory for warning symbols was assessed for younger (18–35 years of age) and older (50–67 years of age) participants. All three conditions paired the symbols with associated text during training; however they differed in the extent to which they further elaborated on the meanings of the symbols. Results: Training substantially improved accuracy and speed of responding on a comprehension test; however there was little difference among conditions. Additionally, while the magnitude of the training effect was similar for both age groups, older participants performed much more poorly than younger participants, both before (37% vs. 52% correct) and after training (68% vs. 88% correct on the immediate post-test), and found it more difficult to reject incorrect meanings (55% vs. 68% correct). Conclusion: Relatively simple training conditions can dramatically improve accuracy and speed of responding to warning symbols. Impact on industry: Training should be used to improve warning symbol comprehension since failures to adequately understand warning information may lead to injury or death. Furthermore, attempts should be made to address individual differences in warning processing such as those related to changes in cognitive processing across the lifespan.     

基于Mapgis技术的地质灾害气象预警系统研究

我国处于特殊的地质构造部位,地质灾害分布广、类型多、频度高、强度大,特别是临近汛期,集中降雨诱发多起崩塌、滑坡、泥石流等地质灾害,造成了严重的人员伤亡及经济损失。在对汛期地质灾害的防灾减灾研究中,发现基于MapGis技术的地质灾害预警系统是重要的防灾措施之一。根据区域地质灾害的空间属性特征和同期常规气象资料,分析了河南省西部山区地质构造特征及地质灾害发育规律,讨论了气象与地质灾害之间的内在联系,在此基础上引入并优化"α～β"建模理论方法,建立了汛期地质灾害气象预警判据,并且基于Mapgis技术开发出河南省汛期地质灾害气象预警系统。通过2004年汛期的初步测试,证明该系统具有较好的地质灾害预警预报功能。     

Forward collision warning based on a driver model to increase drivers’ acceptance

Abstract

Objective: Systems that can warn the driver of a possible collision with a vulnerable road user (VRU) have significant safety benefits. However, incorrect warning times can have adverse effects on the driver. If the warning is too late, drivers might not be able to react; if the warning is too early, drivers can become annoyed and might turn off the system. Currently, there are no methods to determine the right timing for a warning to achieve high effectiveness and acceptance by the driver. This study aims to validate a driver model as the basis for selecting appropriate warning times. The timing of the forward collision warnings (FCWs) selected for the current study was based on the comfort boundary (CB) model developed during a previous project, which describes the moment a driver would brake. Drivers’ acceptance toward these warnings was analyzed. The present study was conducted as part of the European research project PROSPECT (“Proactive Safety for Pedestrians and Cyclists”).

Methods: Two warnings were selected: One inside the CB and one outside the CB. The scenario tested was a cyclist crossing scenario with time to arrival (TTA) of 4?s (it takes the cyclist 4?s to reach the intersection). The timing of the warning inside the CB was at a time to collision (TTC) of 2.6?s (asymptotic value of the model at TTA = 4?s) and the warning outside the CB was at TTC = 1.7?s (below the lower 95% value at TTA = 4?s). Thirty-one participants took part in the test track study (between-subjects design where warning time was the independent variable). Participants were informed that they could brake any moment after the warning was issued. After the experiment, participants completed an acceptance survey.

Results: Participants reacted faster to the warning outside the CB compared to the warning inside the CB. This confirms that the CB model represents the criticality felt by the driver. Participants also rated the warning inside the CB as more disturbing, and they had a higher acceptance of the system with the warning outside the CB. The above results confirm the possibility of developing wellsaccepted warnings based on driver models.

Conclusions: Similar to other studies’ results, drivers prefer warning times that compare with their driving behavior. It is important to consider that the study tested only one scenario. In addition, in this study, participants were aware of the appearance of the cyclist and the warning. A further investigation should be conducted to determine the acceptance of distracted drivers.     

应急预警即时指令技术有效遏制事故发生

在化工企业中通过系统科学辨识危险源,针对危险源安全控制数据,采用OPC通讯接口标准,利用网关机和防火墙隔离技术,实现安全的与生产系统数据链接,建成危险源实时监控与应急预警信息系统的有效链接;通过Web实时画面对现场危险源数据进行监控,数据出现波动立即启动相应预案中的应急措施,利用移动公司的企信通服务,利用面向对象语言采用Socket接口编程,自主开发短信模块接口程序;通过系统调用预警模块实现短信监报功能,应用短信瞬间发布应急预警指令,为应急处理赢得时间,有效地遏制安全生产事故的发生。     

Design and cognitive evaluation of 6 dynamic lane departure warning symbols

Objective: Lane departure, caused by inattention, distraction, drowsiness, or any unusual driver behavior, is a typical risk threatening the driver as well as other road users. Accurate perception of such situations through effective warnings would help drivers to avoid serious consequences. With regard to critical functions of warning symbols for risk communication, the present study focused on providing effective and easily perceivable symbols, compatible with human cognitive capabilities. Thus, the main purpose of the present study was to design and cognitively appraise 6 newly designed dynamic symbols, candidates for a new type of lane departure warning system.

Methods: Simplicity, familiarity, concreteness, meaningfulness, and semantic closeness were the major assessment criteria, defining cognitive features by the earlier researchers in the field. A total number of 187 driving license applicants, with a mean age of 20.58 years (SD = 3.20), participated in the present survey. The participants rated cognitive features of the 6 dynamic symbols along a 0–100 scale.

Results: Significant main effect of the element factor type of the designed symbols on rating cognitive features revealed that the existence of car element was the best predictor for illustrating lane departure. The interaction of both element factor and location of element factor significantly affected the ratings. However, the location of element factor did not solely have any strong effect on the ratings. The results also demonstrated that semantic closeness received the highest overall mean score across symbols (M = 61.80), especially within the symbols that include the car element (M = 75.67). Moreover, a significant difference was observed between the average ratings of the cognitive features, despite the fact that a significant correlation was found between cognitive features.

Conclusion: The most considerable result of the current study was the match between the symbol with the highest ratings and the International Organization for Standardization (ISO)-related icon in appearance. Because previous studies demonstrated a strong correlation between comprehension scores of the symbol and both semantic closeness and meaningfulness, high-level comprehensibility of the best ranked symbol is expected.     

Building Safety indicators: Part 2 – Application,practices and results

Petroleum exploration and production in the Barents Sea is a controversial topic. The Goliat field outside the northern coast of Norway will be the first offshore oil development in this region, with planned production start in 2013–2014. Avoiding major accidents at Goliat is critical; not only to reduce the risks to human lives and the environment, but also to gain political acceptance. Providing early warnings of major accidents for Goliat is one of the main objectives of the research project ‘Building Safety’. The objective of this paper is to describe the development of early warnings in the form of indicators. In addition, the paper includes an overview of current status of early warnings of accidents in other major hazard industries; the nuclear power industry, the chemical process industry, and aviation. Experiences from these industries, including lessons learned from recent major accidents, have been used as important input to the development of early warning indicators.     

Improving the effectiveness of warnings by increasing the appropriateness of their information content: some hypotheses about human compliance

The ways that warnings are administered vary greatly. A warning may come as a message broadcast on the radio about severe weather, as a flashing light in the cockpit of an airplane, or as an audible smoke alarm. Typically, warnings provide an auditory or visual signal to assist in the detection of an anticipated stimulus. However, warnings tend to operate in an all or none mode: either the warning is present, or it is not. Consequently, the information they provide is limited. If warnings are provided too often, their information content becomes even lower and frequent false alarms render them ineffective because of the “cry-wolf” effect. On the other hand, if warnings are not administered frequently enough, they result in too many potentially costly misses. In this conceptual paper, it is argued that the effectiveness of warnings might be significantly improved if warnings are made more “intelligent” by providing information about the likelihood of the occurrence of the stimulus. Several representative cases are discussed and analyzed in order to demonstrate the advantages of the proposed methods.     

The concept of degraded images applied to hazard recognition training in mining for reduction of lost-time injuries

Introduction: This paper discusses the application of a training intervention that uses degraded images for improving the hazard recognition skills of miners. Method: NIOSH researchers, in an extensive literature review, identified fundamental psychological principles on perception that may be employed to enhance the ability of miners to recognize and respond to hazards in their dangerous work environment. Three studies were conducted to evaluate the effectiveness of the degraded image training intervention. A model of hazard recognition was developed to guide the study. Results: In the first study, miners from Pennsylvania, West Virginia and Alabama, who were taught with the aid of degraded images, scored significantly better on follow-up hazard recognition performance measures than those trained using traditional instructional methodologies. The second and third studies investigated the effectiveness of the training intervention at two mining companies. Data collected over a 3-year period showed that lost-time injuries at mines in Alabama and Illinois declined soon after the training intervention was instituted. Impact on Industry: Further exploration of the hazard recognition model and the development of other interventions based on the model could support the validity of the steps in the hazard recognition model.     

液化石油气储罐爆炸碎片抛射的蒙特卡罗分析

液化石油气发生BLEVE具有极大的危害性,如何对危害性进行定量分析和评估是风险分析评价的重要内容。由于BLEVE的发生具有很大的不确定性,其造成的危害也存在不确定性,这给定量分析评价带来了较大的困难。该文从风险工程学的角度对BLEVE引起的碎片抛射可能对人员造成的危害风险进行了定量分析,对不确定性参数利用有关的资料和数据确定其概率密度分布,并利用蒙特卡罗方法进行模拟,从而计算了碎片抛射范围。对于定量评价BLEVE风险具有重要意义。     

基于危险源的事故致因机理及两极化管理

为提升安全风险预控的水平和有效性,探讨危险源的事故致因机理及其两极化管理思路。将危险源划分为3类,即根源危险源、理论状态危险源和实际状态危险源,其中理论状态危险源又可细分为已辨识状态危险源和未辨识状态危险源。构建危险源的事故致因机理模型,模型表明:控制失效的实际状态危险源和未辨识状态危险源是事故发生的2个主要致因。在此基础上,提出危险源的两极化管理思路,构建危险源两极化管理的实施流程。研究结论表明:企业应从两方面实施安全风险预控,即加强对实际状态危险源的控制,使其演变为事故致因的概率极小化;加强对根源危险源和理论状态危险源的辨识,做到辨识极大化。     

支线机场安全动态预警技术研究

提升支线机场安全管理能力是中国支线机场未来发展面临的一个重大问题,为提高我国支线机场安全管理水平,本文基于系统动态的风险管理思想,针对支线机场安全风险发生随机、动态和系统的特点,结合支线机场安全管理实践,构建了支线机场三维风险识别图,以时间维为主线,空间维为基础,逻辑维为依据,多层次地识别支线机场面临的风险,以提高支线机场风险识别结果的客观性和全面性;将风险概率、风险损失、风险可预测性、风险可控制性纳入了支线机场安全风险分析过程,构建了支线机场安全多维风险评价函数,从而能更系统、全面地对支线机场面临的各种风险因素进行评价;通过上述支线机场风险管理技术的应用,可提高对支线机场安全风险的辨别、分析和控制能力,达到对支线机场安全风险进行实时、动态监控的预警目标,进而减少支线机场安全风险的潜在损失。     

从三类危险源理论看煤矿事故的频发

笔者运用现代安全科学的观点及事故致因理论,简述了危险源的概念、系统结构和两类危险源理论,提出了第三类危险源研究,根据事故案例调研的结果,探讨了三类危险源之间的关系及其事故致因机理模型;进一步深入分析了煤矿事故的三类危险源,阐述了煤矿事故频发的原因及对策,认为应加强危险源基础理论的研究,尤其要加强对煤矿第三类危险源的辨识和控制研究,这对煤矿安全管理水平的提高具有重要意义。     

长大隧道突发性地质灾害预警信息系统研究

针对国内外长大隧道施工过程中频繁遇到的突发性地质灾害(涌水、突泥,以下同)对工程造成重大损失和人员伤亡,调研国内外长大隧道突发性地质灾害发生现状和危害,首次提出隧道突发性地质灾害预测预报方法为灾害发生前兆的现象预报法和S-t曲线变化趋势判断法;并对主要风险源水压和水量、水质、初期支护内力及围岩位移进行监控,给出相应的预警标准。笔者研究并开发了隧道灾害预警系统,在浏阳河隧道过河段现场使用;结果表明,该系统能较好地适应隧道复杂环境,稳定性好,能对采集到的数据分析判别,对长大隧道安全施工具有一定的指导意义。     

Effects of an integrated collision warning system on teenage driver behavior

IntroductionCrash warning systems have been shown to provide safety benefits, but no studies have examined how teenagers respond. This study sought to find out whether young, inexperienced drivers change behavior in response to warnings.MethodsForty 16–17 year-olds drove an instrumented vehicle equipped with a system that warned for lane departures and potential rear-end and lane change/merge crashes. Participants were randomly assigned to experimental or control groups, and their driving was monitored for 14 weeks during 2011–12. For the experimental group, this included a treatment period, when crash alerts were received by drivers, and baseline and post-treatment periods, when warnings were recorded but not received. The control group never received warnings. Data were analyzed to determine whether warnings were associated with changes in driving behavior.ResultsA total of 15,039 trips were analyzed. Lane drifts accounted for 73% of warnings. Forward collision warning rates doubled for all drivers during the treatment period and continued at an increased rate post-treatment. This was likely a result of the fact that, as time went on, all drivers spent more time following vehicles at close distances. Receiving alerts was associated with effects on following and lane-changing behavior, including more time spent following at close distances (17%), fewer lateral drifts (37%) and fewer unsignaled lane changes (80%). Receiving warnings wasn't associated with an increased likelihood of engaging in secondary tasks.ConclusionsWarning systems may result in improved lane-keeping and turn-signal behaviors by novice drivers, but there is some indication they may result in more close-following behaviors.Practical applicationsThere is some evidence that lane departure warning may improve turn-signal use for young drivers. While there is no evidence of safety benefits from the other types of warnings, there is some evidence of an increase in close-following behavior but no increase in secondary tasks due to the presence of those capabilities.     

Overview of GHS (Globally Harmonized System) in Korea and the direction of further development

Many chemicals are being developed with the growth of science technology. Such chemicals bring many advantages to humans but also cause many social problems because of the hazards of the materials. Therefore, it is necessary to have a system which identifies the hazards of chemicals. Some acts or regulations about information on warning labels or MSDS (Material Safety Data Sheet) information for chemicals are similar in each country but there are differences in definitions of degree of hazard, standard classification of harmful level, and indication methods. GHS is the indication method of worldwide integrated classification standard in order to prevent damage caused by disease or risks of accidents resulting from confusion by the users. In keeping pace with the world trend, Korea has conducted translation of the GHS manual from UN and selected it as the official GHS manual of the Korean government. The official Korean GHS translated version was published in July 2005. After that, the Korea Ministry of Employment and Korea Labor and the Ministry of Environment have implemented GHS MSDS for chemical substances since July 1, 2010 so that manufacturers and importers are required to apply it. The full implementation for compound materials will start on July 1, 2013. In Korea, database information for chemicals is provided by four organizations including The Korea Occupational Safety and Health Agency. However, domestic information on chemicals provided by domestic information providers has problems including differences in basic content and incorrect recording because of trade secrets. Efforts for improvement including reinforcing training for manufacturers and importers on recording consistent information for different organizations are urgently needed.     

Comparison of Expected Crash and Injury Reduction from Production Forward Collision and Lane Departure Warning Systems

Objectives: The U.S. New Car Assessment Program (NCAP) now tests for forward collision warning (FCW) and lane departure warning (LDW). The design of these warnings differs greatly between vehicles and can result in different real-world field performance in preventing or mitigating the effects of collisions. The objective of this study was to compare the expected number of crashes and injured drivers that could be prevented if all vehicles in the fleet were equipped with the FCW and LDW systems tested under the U.S. NCAP.

Methods: To predict the potential crashes and serious injury that could be prevented, our approach was to computationally model the U.S. crash population. The models simulated all rear-end and single-vehicle road departure collisions that occurred in a nationally representative crash database (NASS-CDS). A sample of 478 single-vehicle crashes from NASS-CDS 2012 was the basis for 24,822 simulations for LDW. A sample of 1,042 rear-end collisions from NASS-CDS years 1997–2013 was the basis for 7,616 simulations for FCW. For each crash, 2 simulations were performed: (1) without the system present and (2) with the system present. Models of each production safety system were based on 54 model year 2010–2014 vehicles that were evaluated under the NCAP confirmation procedure for LDW and/or FCW. NCAP performed 40 LDW and 45 FCW tests of these vehicles.

Results: The design of the FCW systems had a dramatic impact on their potential to prevent crashes and injuries. Between 0 and 67% of crashes and 2 and 69% of moderately to fatally injured drivers in rear-end impacts could have been prevented if all vehicles were equipped with the FCW systems. Earlier warning times resulted in increased benefits. The largest effect on benefits, however, was the lower operating speed threshold of the systems. Systems that only operated at speeds above 20 mph were less than half as effective as those that operated above 5 mph with similar warning times. The production LDW systems could have prevented between 11 and 23% of drift-out-of-lane crashes and 13 and 22% of seriously to fatally injured drivers. A majority of the tested LDW systems delivered warnings near the point when the vehicle first touched the lane line, leading to similar benefits. Minimum operating speed also greatly affected LDW effectiveness.

Conclusions: The results of this study show that the expected field performance of FCW and LDW systems are highly dependent on the design and system limitations. Systems that delivered warnings earlier and operated at lower speeds may prevent far more crashes and injuries than systems that warn late and operate only at high speeds. These results suggest that future FCW and LDW evaluation should prioritize early warnings and full-speed range operation. A limitation of this study is that additional crash avoidance features that may also mitigate collisions—for example, brake assist, automated braking, or lane-keeping assistance—were not evaluated during the NCAP tests or in our benefits models. The potential additional mitigating effects of these systems were not quantified in this study.