Human Error Rate Research Articles

Cognitive pilot-aircraft interface for single-pilot operations

Considering the foreseen expansion of the air transportation system within the next two decades and the opportunities offered by higher levels of automation, Single-Pilot Operations (SPO) are regarded as viable alternatives to conventional two-pilot operations for commercial transport aircraft. In comparison with current operations, SPO require higher cognitive efforts, which potentially result in increased human error rates. This article proposes a novel Cognitive Pilot-Aircraft Interface (CPAI) concept, which introduces adaptive knowledge-based system functionalities to assist single pilots in the accomplishment of mission-essential and safety-critical tasks in modern commercial transport aircraft. The proposed CPAI system implementation is based on real-time detection of the pilot’s physiological and cognitive states, allowing the avoidance of pilot errors and supporting enhanced synergies between the human and the avionics systems. These synergies yield significant improvements in the overall performance and safety levels. A CPAI working process consisting of sensing, estimation and reconfiguration steps is developed to support the assessment of physiological and external conditions, a dynamic allocation of tasks and adaptive alerting. Suitable mathematical models are introduced to estimate the mental demand associated to each piloting task and to assess the pilot cognitive states. Suitably implemented decision logics allow a continuous and optimal adjustment of the automation levels as a function of the estimated cognitive states. Representative numerical simulation test cases provide a preliminary validation of the CPAI concept. In particular, the continuous adaptation of the flight deck's automation successfully maintains the pilot's task load within an optimal range, mitigating the onset of hazardous fatigue levels. It is anticipated that by including suitably designed Psychophysiological-Based Integrity Augmentation (PBIA) functionalities the CPAI system will allow to fulfil the evolving aircraft certification requirements and hence support the implementation of SPO in commercial transport aircraft.

M-Health for Improving Screening Accuracy of Acute Malnutrition in a Community-Based Management of Acute Malnutrition Program in Mumbai Informal Settlements.

Acute malnutrition is linked to child mortality and morbidity. Community-Based Management of Acute Malnutrition (CMAM) programs can be instrumental in large-scale detection and treatment of undernutrition. The World Health Organization (WHO) 2006 weight-for-height/length tables are diagnostic tools available to screen for acute malnutrition. Frontline workers (FWs) in a CMAM program in Dharavi, Mumbai, were using CommCare, a mobile application, for monitoring and case management of children in combination with the paper-based WHO simplified tables. A strategy was undertaken to digitize the WHO tables into the CommCare application. To measure differences in diagnostic accuracy in community-based screening for acute malnutrition, by FWs, using a mobile-based solution. Twenty-seven FWs initially used the paper-based tables and then switched to an updated mobile application that included a nutritional grade calculator. Human error rates specifically associated with grade classification were calculated by comparison of the grade assigned by the FW to the grade each child should have received based on the same WHO tables. Cohen kappa coefficient, sensitivity and specificity rates were also calculated and compared for paper-based grade assignments and calculator grade assignments. Comparing FWs (N = 14) who completed at least 40 screenings without and 40 with the calculator, the error rates were 5.5% and 0.7%, respectively (p < .0001). Interrater reliability (κ) increased to an almost perfect level (>.90), from .79 to .97, after switching to the mobile calculator. Sensitivity and specificity also improved significantly. The mobile calculator significantly reduces an important component of human error in using the WHO tables to assess acute malnutrition at the community level.

Categorization and standardization of accidental risk-criticality levels of human error to develop risk and safety management policy

In addition to increasing mechanization, technology upgradation and process automation, safety enhancement in systems operation is one of the key parameters of productivity improvement. Now, it is an established fact that human error plays a crucial role in accidents and needs to be addressed adequately in risk and safety management. This paper aims at assessing, categorizing and setting standards for human error risk and criticality of system activities. Based on the classification and standardizations of human error rate, consequences of human error and criticality index of errors, different policy decisions for risk and safety management are suggested. The proposed methodology has been demonstrated with reference to the system activities of an underground coal mining system. However developed method can be equally adapted to other systems.

モバイルデータ通信を利用した遠隔地における航行情報表示システム

This study proposes the marine navigation support system which provides video images and states around the target vessel. Approximately 80 percent factors of marine traffic accident is human error when we check the report for the last 5 years. Due to the shortage of domestic vessel crew and the human cost cutting, the number of domestic vessel crew has been decreasing and the rate of human error has been increasing. In order to lighten the work load of crew, we designed the system which supports watching from a distant place. Because of taking a high cost, video streaming between the ship and the land is difficult. In this paper, we achieved low delay video streaming at low cost from the cameras which installed at vessel main mast at by mobile data communications. In addition to video distribution, we get the data from nautical instruments and AIS. Owing to display these information on video images, we propose the displaying navigation status system which can grasp the states around the target vessel at a low delay from the land.

Semi-automation of Doppler Spectrum Image Analysis for Grading Aortic Valve Stenosis Severity.

Doppler echocardiography analysis has become a golden standard in the modern diagnosis of heart diseases. In this paper, we propose a set of techniques for semi-automated parameter extraction for aortic valve stenosis severity grading. The main objectives of the study is to create echocardiography image processing techniques, which minimize manual image processing work of clinicians and leads to reduced human error rates. Aortic valve and left ventricle output tract spectrogram images have been processed and analyzed. A novel method was developed to trace systoles and to extract diagnostic relevant features. The results of the introduced method have been compared to the findings of the participating cardiologists. The experimental results showed the accuracy of the proposed method is comparable to the manual measurement performed by medical professionals. Linear regression analysis of the calculated parameters and the measurements manually obtained by the cardiologists resulted in the strongly correlated values: peak systolic velocity's and mean pressure gradient's R2 both equal to 0.99, their means' differences equal to 0.02 m/s and 4.09 mmHg, respectively, and aortic valve area's R2 of 0.89 with the two methods means' difference of 0.19 mm. The introduced Doppler echocardiography images processing method can be used as a computer-aided assistance in the aortic valve stenosis diagnostics. In our future work, we intend to improve precision of left ventricular outflow tract spectrogram measurements and apply data mining methods to propose a clinical decision support system for diagnosing aortic valve stenosis.

Development of an Excel-based laboratory information management system for improving workflow efficiencies in early ADME screening.

There is a clear requirement for enhancing laboratory information management during early absorption, distribution, metabolism and excretion (ADME) screening. The application of a commercial laboratory information management system (LIMS) is limited by complexity, insufficient flexibility, high costs and extended timelines. An improved custom in-house LIMS for ADME screening was developed using Excel. All Excel templates were generated through macros and formulae, and information flow was streamlined as much as possible. This system has been successfully applied in task generation, process control and data management, with a reduction in both labor time and human error rates. An Excel-based LIMS can provide a simple, flexible and cost/time-saving solution for improving workflow efficiencies in early ADME screening.

Modelling worker reliability with learning and fatigue

A mathematical model is developed that estimates the human error rate while performing an assembly job under the influence of learning–forgetting and fatigue–recovery. Despite other Human Reliability Analysis (HRA) models that are not capable of anticipating how and when an error occurs, this model is able to dynamically measure the human error rate and reliability with time. An experimental analysis is performed to examine the effect of the model parameters on the error rate and the model behaviour is investigated through five research questions. Numerical examples are provided to illustrate the results.

An integrated method for human error probability assessment during the maintenance of offshore facilities

The paper presents a novel approach for Human Error Probability (HEP) assessment by integrating the Success Likelihood Index Method (SLIM) with the Technique of Human Error Rate Prediction (THERP). In this approach, the SLIM has been embedded within the THERP framework to generate the nominal HEP data when it is unavailable. The developed methodology is implemented to an offshore condensate pump maintenance task. In the first step of this study, the human error was estimated considering all the standard tools and procedures which are in place. In the second step, as an additional measures, radio frequency identification (RFID) based tools are utilized and HEP is recalculated. Without the application of RFID tools, the HEP value is found to be 5.7244×1022 or estimated as 5.72% with an uncertainty bound of 1.1448×10−2–1.1452×10−1. With RFID tools, it is reduced to 4.6342×10−2 or 4.63%, with an uncertainty bound of 2.145×10−2–2.089×10−1 which yields a net HEP reduction of 1.09%.

The impact of computer-based procedures on team performance, communication, and situation awareness

In nuclear power plants, operating procedures are adopted to aid the operators in performing their tasks. With the evolution of computer hardware and software, the analog human-machine systems of the main control room in the nuclear power plant have been replaced with digital systems. Moreover, automated operations now outnumber manual operations. The purpose of this study was to evaluate the impact of computer-based procedures on the team performance, communication, and situation awareness of operators in the main control room. To achieve the purpose, a within-subjects experiment was designed and then a survey was conducted. The results showed that the teams had better objective performance and higher situation awareness when using computer-based procedures. In addition, the teams also had lower human error and lower communication rates when using computer-based procedures. This study proposes that computer-based procedures are advantageous to the operation of the systems of the main control rooms in nuclear power plants. Relevance to industryComputerized procedures system is one of the specific features for advanced nuclear power plant. This study explores and analyzes the team performance, communication, and situation awareness difference between paper-based, electronic, and computer-based procedures in detail. It may provide practical information for how to apply computer-based procedures to perform the tasks in the main control room of the advanced nuclear power plant.

The Methodology for the Selection of the Appropriate Sensory Equipment for the Grasping End Effectors in the Assembly Workspace

Nowadays, there is a huge emphasis on the development of devices, technologies and process in the industry. Automation helps with it in the considerable degree, because it tries to solve the development of technique, what is characteristic sign of production, assembly, control and another process realization, what eliminates the human intervention and error rates. Automated assembly process consists of the assembly and handling operations of component connecting to the different units and final products, what is equipped with appropriate devices to eliminate the human intervention. One of the most productive solutions seems to be the deployment and the use of robots and manipulators, which realize the technological, handling and also transporting process. This contribution deals with the systematic steps for the selection of the appropriate sensory equipment used in the gripping robotic end effectors, which are characteristic for the assembly system, placed in our department laboratories.

Validating THERP: Assessing the scope of a full-scale validation of the Technique for Human Error Rate Prediction

Science-based Human Reliability Analysis (HRA) seeks to experimentally validate HRA methods in simulator studies. Emphasis is on validating the internal components of the HRA method, rather than the validity and consistency of the final results of the method. In this paper, we assess the requirements for a simulator study validation of the Technique for Human Error Rate Prediction (THERP), a foundational HRA method. The aspects requiring validation include the tables of Human Error Probabilities (HEPs), the treatment of stress, and the treatment of dependence between tasks. We estimate the sample size, n, required to obtain statistically significant error rates for validating HEP values, and the number of observations, m, that constitute one observed error rate for each HEP value. We develop two methods for estimating the mean error rate using few observations. The first method uses the median error rate, and the second method is a Bayesian estimator of the error rate based on the observed errors and the number of observations. Both methods are tested using computer-generated data. We also conduct a pilot experiment in The Ohio State University’s Nuclear Power Plant Simulator Facility. Student operators perform a maintenance task in a BWR simulator. Errors are recorded, and error rates are compared to the THERP-predicted error rates. While the observed error rates are generally consistent with the THERP HEPs, further study is needed to provide confidence in these results as the pilot study sample size is small. Sample size calculations indicate that a full-scope THERP validation study would be a substantial but potentially feasible undertaking; 40h of observation would provide sufficient data for a preliminary study, and observing 101 operators for 20h each would provide data for a full validation experiment.

Applications of integrated human error identification techniques on the chemical cylinder change task

This paper outlines the human error identification (HEI) techniques that currently exist to assess latent human errors. Many formal error identification techniques have existed for years, but few have been validated to cover latent human error analysis in different domains. This study considers many possible error modes and influential factors, including external error modes, internal error modes, psychological error mechanisms, and performance shaping factors, and integrates several execution procedures and frameworks of HEI techniques. The case study in this research was the operational process of changing chemical cylinders in a factory. In addition, the integrated HEI method was used to assess the operational processes and the system's reliability. It was concluded that the integrated method is a valuable aid to develop much safer operational processes and can be used to predict human error rates on critical tasks in the plant.

Wrong blood in tube - potential for serious outcomes: can it be prevented?

'Wrong blood in tube' (WBIT) errors, where the blood in the tube is not that of the patient identified on the label, may lead to catastrophic outcomes, such as death from ABO-incompatible red cell transfusion. Transfusion is a multistep, multidisciplinary process in which the human error rate has remained unchanged despite multiple interventions (education, training, competency testing and guidelines). The most effective interventions are probably the introduction of end-to-end electronic systems and a group-check sample for patients about to receive their first transfusion, but neither of these eradicates all errors. Further longer term studies are required with assessment before and after introduction of the intervention. Although most focus has been on WBIT in relation to blood transfusion, all pathology samples should be identified and linked to the correct patient with the same degree of care. Human factors education and training could help to increase awareness of human vulnerability to error, particularly in the medical setting where there are many risk factors.

Surface micropattern limits bacterial contamination.

BackgroundBacterial surface contamination contributes to transmission of nosocomial infections. Chemical cleansers used to control surface contamination are often toxic and incorrectly implemented. Additional non-toxic strategies should be combined with regular cleanings to mitigate risks of human error and further decrease rates of nosocomial infections. The Sharklet micropattern (MP), inspired by shark skin, is an effective tool for reducing bacterial load on surfaces without toxic additives. The studies presented here were carried out to investigate the MP surfaces capability to reduce colonization of methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) compared to smooth control surfaces.MethodsThe MP and smooth surfaces produced in acrylic film were compared for remaining bacterial contamination and colonization following inoculation. Direct sampling of surfaces was carried out after inoculation by immersion, spray, and/or touch methods. Ultimately, a combination assay was developed to assess bacterial contamination after touch transfer inoculation combined with drying (persistence) to mimic common environmental contamination scenarios in the clinic or hospital environment. The combination transfer and persistence assay was then used to test antimicrobial copper beside the MP for the ability to reduce MSSA and MRSA challenge.ResultsThe MP reduced bacterial contamination with log reductions ranging from 87-99% (LR = 0.90-2.18; p < 0.05) compared to smooth control surfaces. The MP was more effective than the 99.9% pure copper alloy C11000 at reducing surface contamination of S. aureus (MSSA and MRSA) through transfer and persistence of bacteria. The MP reduced MSSA by as much as 97% (LR = 1.54; p < 0.01) and MRSA by as much as 94% (LR = 1.26; p < 0.005) compared to smooth controls. Antimicrobial copper had no significant effect on MSSA contamination, but reduced MRSA contamination by 80% (LR = 0.70; p < 0.005).ConclusionThe assays developed in this study mimic hospital environmental contamination events to demonstrate the performance of a MP to limit contamination under multiple conditions. Antimicrobial copper has been implemented in hospital room studies to evaluate its impact on nosocomial infections and a decrease in HAI rate was shown. Similar implementation of the MP has potential to reduce the incidence of HAIs although future clinical studies will be necessary to validate the MP’s true impact.

Inclusion of task dependence in human reliability analysis

Dependence assessment among human errors in human reliability analysis (HRA) is an important issue, which includes the evaluation of the dependence among human tasks and the effect of the dependence on the final human error probability (HEP). This paper represents a computational model to handle dependence in human reliability analysis. The aim of the study is to automatically provide conclusions on the overall degree of dependence and calculate the conditional human error probability (CHEP) once the judgments of the input factors are given. The dependence influencing factors are first identified by the experts and the priorities of these factors are also taken into consideration. Anchors and qualitative labels are provided as guidance for the HRA analyst׳s judgment of the input factors. The overall degree of dependence between human failure events is calculated based on the input values and the weights of the input factors. Finally, the CHEP is obtained according to a computing formula derived from the technique for human error rate prediction (THERP) method. The proposed method is able to quantify the subjective judgment from the experts and improve the transparency in the HEP evaluation process. Two examples are illustrated to show the effectiveness and the flexibility of the proposed method.

Integration of HOFs into ATEX Risk Assessment Methodology

The current ATEX (Explosive Atmosphere) risk assessment methodology relies on a semi-quantitative approach based on the following indexes: probability of an explosive atmosphere formation, probability of the presence of an effective ignition source and consequences. The whole risk assessment procedure can be separated into four steps ---- area classification, ignition sources identification, consequence analysis, and risk evaluation. However, when reviewing the whole ATEX risk assessment procedures and their results, despite many operations on plant and equipment containing dangerous substances are performed by operators, the human and organizational influences are neglected. The study proposed in this paper is to develop an ATEX risk assessment methodology with the integration of human and organizational factors (HOFs), in order to provide an advanced methodology able to analyse the HOFs influences on ATEX hazards. The developed ATEX risk assessment methodology introduces in the procedure the Technique for Human Error Rate Prediction (THERP) to identify human and organizational weaknesses, and also provides a tool for calculating the human error probability (HEP) in the first two risk steps ---- area classification and ignition sources identification. During the risk evaluation procedure, human risk level, based on the results of HEP, has been introduced into the original ATEX risk assessment methodology.

On the operator action analysis to reduce operational risk in research reactors

Human errors during operation and the resulting increase in operational risk are major concerns for nuclear reactors, just as they are for all industries. Additionally, human reliability analysis together with probabilistic risk analysis is a key element in reducing operational risk. The purpose of this paper is to analyze human reliability using appropriate methods for the probabilistic representation and calculation of human error to be used alongside probabilistic risk analysis in order to reduce the operational risk of the reactor operation. We present a technique for human error rate prediction and standardized plant analysis risk. Human reliability methods have been utilized to quantify different categories of human errors, which have been applied extensively to nuclear power plants. The Tehran research reactor is selected here as a case study, and after consultation with reactor operators and engineers human errors have been identified and adequate performance shaping factors assigned in order to calculate accurate probabilities of human failure.

2309 Human Error and Production Rate Correlation in Assembly Process of Electronics Goods

2309 Human Error and Production Rate Correlation in Assembly Process of Electronics Goods

Assessment of Flight Crew Errors Based on THERP

The purpose of this study is to reduce the aviation accidents and incidents induced by flight crew errors. A flight crew errors analysis and classification system is developed preliminary. In combination with aviation flight accidents exploration, and interviews with pilots, the human error modes which will occur in the flight task are identified. A quantitative method to assess flight crew errors is established on Technique For Human Error Rate Prediction (THERP). In a case study, the takeoff task is analyzed, the human error modes and consequences are identified, and the failure probability of takeoff task is calculated. Those results are useful for SSA (System Safety Assessment) to improve the aircraft safety design.

Upstairs and Downstairs

Under cricket’s decision review system (DRS) a player may request a review of dismissal decisions taken by on-field umpires. Reviews of leg before wicket decisions, the focus of this article, occur through a ball-tracking technology popularly called “Hawk-Eye.” If Hawk-Eye makes mistakes, in the face of such errors, the overall error rate can be decomposed into a “technology error rate” and a “human error rate.” Consequently, improved decision can be achieved through better technology or better umpires. We argue that, given the costs of DRS, the same gains could be obtained, at lower cost, by investing in umpires rather than technology.