bluuebunny/crossref_metadata_2025 huggingface dataset:
Representative Auditory Warning Signals: Methodological Considerations for Their Development and Selection
Authors: Belz S.M. , Winters J.J. , Robinson G.S. , Casali J.G.
Published: January 2012

The work focuses on an initial effort to develop a selection methodology (Free Meaning Response, Perceived Urgency, and Perceived Association with an experimenter-selected meaning) for representative auditory warnings, also known as “auditory icons”, a new class of auditory warning signals. Further, the need to consider population differences and testing environment when using the above methodology is experimentally demonstrated. Finally, hypotheses related to situations where representative auditory warning signals may/may not be most effective, specifically, issues related to masking (when the noise and signal spectra are similar) and the conveyance of abstract ideas (very difficult with auditory icons) are presented.
Connoted Hazard of Voiced Warning Signal Words: An Examination of Auditory Components
Authors: Hollander Todd D. , Wogalter Michael S.
Published: January 2012

Signal words, such as DANGER and WARNING have been used in print (visual) warnings with the intention of evoking different levels of perceived hazard. However, there is limited research on whether auditory presentation of these words connote different levels of perceived hazard. In the present study, five voiced signal words were used to produce sound clips each composed of the words spoken three times and were manipulated according to the following factors: speaker gender, word unit duration (fast, slow), inter-word interval, (short, long), with the sound level held constant. Results indicate that the sound clips with short word unit duration were given higher carefulness ratings than long word unit duration ( ps < .01). The results showed a similar pattern of ratings for the signal words as shown in research using print presentations. Implications for the design of voiced warnings are described.
Issues Relating to the Conduct of Empirical Research into the Detection of Auditory Stimuli in Noise When Wearing Nontraditional Hearing Protectors
Authors: Robinson Gary S. , Casali John G.
Published: January 2012

Nontraditional hearing protection devices are intended to improve the audibility of auditory stimuli in noisy environments. However, when tested in controlled laboratory settings, such benefits are not always apparent. The characteristics of active noise reduction, amplitude-sensitive, and other augmented HPDs are briefly described. Next, the results of past research are discussed, as are the reasons why such results are not always as expected. Finally, methodological issues encountered when conducting auditory detection studies using nontraditional hearing protection will be addressed, including choice of noise spectra, workload, and psychophysical methods.
Embedded ASR: Lessons Learned Integrating Speech Control into Embedded Systems
Authors: Fisher Francis (Pete)
Published: January 2012

For the most basic embedded systems, an integrator must assume that the system has no keyboard support, no mouse, and no monitor. A programmable keypad and a limited alphanumeric display are the usual interface devices. Our research looks at the new generation of powerful embedded platforms and operating systems to investigate the potential integration of automatic speech recognition (ASR) to control high-end diagnostic systems. Our goal is to present a working design model and identify critical issues to aid future designers and system engineers in the process of incorporating speech control into embedded systems. Critical issues discussed include hardware platforms, use of off-the-shelf ASR software, real-time versus near-real-time operating systems, and user system navigation and location awareness.
Preparing the Aircraft Maintenance Technician for Tomorrow: Assessment of the New AMT Curriculum
Authors: Arnold Doyle , Gramopadhye Anand K. , Bingham Jamie , Master Reena , Quadros Nitin
Published: January 2012

The aviation maintenance technician (AMT) is a critical component in ensuring the safety and reliability of the aircraft maintenance operations. Hence it is critical that students AMT's receive proper education and training that will prepare them for work in the hangar floor. Realizing this, a newly integrated curriculum for student AMT's was developed. This paper outlines the methodology that was used to assess the revised AMT curriculum that integrates alternative learning methodologies, and previous FAA sponsored human factors research into a coherent whole. The paper describes the assessment methodology, which was used to test how the curriculum helps meet educational objectives and student performance objectives.
The Impact on Safety of Computerized Control Room in Nuclear Power Plants: The French Experience on Human Factors with N4 Series
Authors: Tasset Daniel , Labarthe Jean-Paul
Published: January 2012

The French N4 reactor series is the new generation of reactors in France. One of its innovations consists in a computerized man-machine operating system, that has some impact on operation in normal as well as in incident and accident situation. This paper describes how human factors aspects are taken into account during the safety assessment and approval process, and what main lessons can be gained from this experience as regards human factors and safety in the design and evaluation of a computerized control room.
Ergonomic and Psychological Provisions of a Power Plant
Authors: Zhuravlyov G.E. , Sakov B.A.
Published: January 2012

The report is describing an experience of the ergonomic and psychological works performed at the Power Plant #25, Mosenergo Co. during last 12 years. The report aims to achieve two connected goals:

- to insert additional elements into the power plant functional structure - to propose solutions to some Human Factors problems
Mental Fatigue and Workload: Effort Allocation during Multiple Task Performance
Authors: Stark Julie M. , Scerbo Mark W. , Freeman Frederick G. , Mikulka Peter J.
Published: January 2012

The goal of the present study was to gain a better understanding of the effect of mental fatigue and workload on allocation of effort during prolonged multiple task performance was examined. Two levels of workload were manipulated between subjects. Time was assessed over three consecutive 30-min periods. Performance was measured on the Multi-Attribute Task Battery which was revised to include a new task. This new task was developed to investigate allocation of effort to various activities over time. A 2 (workload) X 3 (time) mixed factorial design was employed. The most dramatic shifts in allocation of effort were observed for the high workload participants. For these individuals, performance on several tasks suffered in the third period. These results suggest that varying workload in a multi-tasking situation can not only affect performance on concurrent tasks but also the allocation of effort over time.
Work Strain, Work Ability and Health When Changing from an Old to a New Slaughter
Authors: Clas-Håkan Nygård , Marita Pitkänen , Marja-Liisa Manka , Heikki Arola
Published: January 2012

The aim of present study was to evaluate the effects of a change into a new chicken slaughter on the perceived work strain and capacities of the workers. In the old factory and in the new factory workers answered a questionnaire about work strain and health. The results suggested that moving into the new factory caused in general no changes in strain among the workers, although the perceived capacity and health decreased. There were more changes among the older than among the younger workers in both perceived work strain and capacities. The results could partly be explained by increased productivity, difficulties in the production technique, changes in the management and that some of the planned actions could not be realised.
The Age Characteristics of Chronic Musculoskeletal Disorders among Chinese Workers
Authors: Yongmei Li Tianlin Yu , Shuxiang Jin , Hong Chen , Ruli Qin , Yanqin Li , Iefen Zhang
Published: January 2012

The tenderness in wrist, lower arm, shoulder, upper back and low back are often caused by chronic muskuloskeletal disorder of the whole body or the part of the body, it is an important cause of morbidity and absenteeism in the occupational environment. So we decide to study this problem among 2034 workers of assembly line in six different industries (car, clothing, machinery, electronic, computer and post office) and 580 workers selected from a control group who worked in the same factories with equivalent activities. The results of this study showed that the percentage on tenderness in the parts of the body mentioned above increase with the adding of the workers age; In general, the percentage on tenderness of workers with ≥35 age group always keep the highest level.
Work, Age and the Perception of Age among Workers in Five Nations
Authors: Barnes-Farrell Janet L. , Rumery Steven M.
Published: January 2012

Health care workers from five nations (Brazil, Croatia, Poland, Ukraine, USA) completed the Survey of Health Care Professionals, which includes measures of on-the-job and off-the-job conditions/concerns, as well as self-ratings of work demands, work skills and performance, work-related stress and measures of chronological and personal age. Consistent with previous research, feeling old relative to one's chronological age was positively associated with several indicators of experienced job-related stress; the magnitude of the relationships differed among national samples. Findings support further investigation of this operationalization of personal age as an indicator of unrelieved stress. Levels of concern about stressful workplace conditions and stressful off-the-job conditions (survival needs, home environment, and societal stressors) also differed among nations. In addition, our analyses revealed interesting similarities and differences among nations in the patterns of relationships between stressful workplace/off-the-job conditions and personal age.
Aging, Executive Function, and Human Factors
Authors: Elias Jeffrey W. , Clelland Zoe
Published: January 2012

Over the past decade the role of executive function (ECF) in behavioral assessments has become well-known in the neurological and cognitive aging literature. With the exception of working memory, the assessment of ECF and situations that might enhance or detract from ECF have received little focus in human factors work. Part of this omission stems from a lack of understanding of the scope of ECF as it affects behavior, and lack of a well-known means of quickly assessing or screening for ECF failure. A framework for understanding ECF as it relates to human factors is presented and follows the acronym SOS-MOMMI. The discussion follows the role of selection, organization, sequencing, monitoring, mentoring (self), working memory, and inhibition as components of the ECF system that are affected by age, fatigue, stress, depression, and alcohol use. Examples of ECF failures and conditions that produce them are discussed as well as brief screens that can be used to gather data to assess ECF
Extending Knowledge of the Effects of Social Influence in Warning Compliance
Authors: Edworthy Judy , Dale Stephen
Published: January 2012

Three experiments are reported which measure the effects of social influence on participants' willingness to use protective equipment when carrying out a paint-spraying task within a laboratory setting. The first study established baseline compliance levels in both low-cost and high-cost conditions. The second study showed that compliance levels are greater when a single confederate also uses the protective equipment, and lower when the confederate does not use the equipment. The third study shows that a larger group of confederates, where only the majority comply or do not comply, can also influence participant compliance in the same way.
Pain and Suffering Awards for Consumer Product Accidents: Effects of Plaintiff-Defendant Liability and Injury Severity
Authors: Laughery Kenneth R. , Laughery Brenda R. , Meingast Melissa E. , Bean Richard N. , Wogalter Michael S.
Published: January 2012

A study was carried out to explore the effects of two variables on the amount of pain and suffering awards in a product liability litigation context. The first variable was the level of liability/responsibility allocated to the plaintiff and defendant for the accident and injury. The two levels were 100% and 60% assigned to the defendant, with the corresponding levels for the plaintiff at 0% and 40%. The second variable was the severity of the injury which was characterized as high or low. The two variables were manipulated between participants, resulting in a 2 × 2 design. Four separate accident/injury scenarios were employed, and each participant was presented with all four scenarios in one of the conditions. The scenarios described an automobile accident resulting in paralysis, a workplace accident resulting in chemical burns, a workplace accident resulting in brain damage, and an automobile accident resulting in the death of a small child. Following the presentation of each scenario, participants were asked to make a pain and suffering award. There were no constraints, small or large, on the size of the awards. Results indicated significant differences in pain and suffering allocations for the two levels of liability/responsibility (means in dollars were: defendant 100% = 4.0 million, defendant 60% = 1.2 million). While the means were in the expected direction for the high and low injury severity manipulation (high = 3.2 million, low = 2.0 million) the difference in pain and suffering allocations was not significant. The results suggest that liability or fault may play an important role in pain and suffering awards, a finding of significance in understanding jury decisions.
Emphasizing Non-Obvious Hazards Using Multi-Frame Pictorials and Color on Allocation of Blame
Authors: Williams Kevin J. , Kalsher Michael J. , Maru Michelle , Wogalter Michael S.
Published: January 2012

This study examined allocations of blame for injuries sustained from the consumption of a product with a non-obvious hazard. Participants were given product-use scenarios that described a girl whose age was manipulated to be from 18 months to 16 years and who suffered serious brain damage after choking on a marshmallow made available to her by her mother. Supplementary information intended to be either positive or detrimental to the manufacturer and its safety practices was either present or absent from the scenario. When present and positive, the manufacturer put a warning on the product about the non-obvious hazard. The warning was manipulated by having color or not and a multi-frame or single-frame pictorial. Results replicated findings reported initially by Kalsher et al. (1999). When supplementary information was positive or not provided, participants directed more blame toward the parents of the young victim and less to the manufacturer. The opposite pattern was shown when negative supplementary information about the manufacturer and its safety practices was provided, suggesting that people perceived the manufacturer as irresponsible in their practices.
Clinical Validation of the Ansi C63.19 Draft Standard for Measuring Compatibility between Digital Wireless Phones and Hearing Aids
Authors: Schlegel Robert E. , Grant Hank , Fry Tamy L.
Published: January 2012

Acoustic interference can be generated in hearing aids by the pulsed transmission signal of a digital wireless phone. This interference, resembling a buzzing, clicking, or static sound, is annoying and can seriously degrade the intelligibility of the speech. The objective of the ANSI C63.19 Draft Standard is to provide a simple, reliable test procedure for measuring the immunity of hearing aids to this interference. To clinically validate the standard, hearing aids were custom manufactured for eighteen hearing-impaired participants. The participants rated the effects of the interference experienced when using five digital wireless phone technologies (CDMA at 800 and 1900 MHz, TDMA-50 Hz at 800 and 1900 MHz, and TDMA-217 Hz at 1900 MHz) at five transmission power levels (0, 6, 12, 18, and 24 dBm). More than two-thirds of the subjects responded as predicted by acoustic measurements of the interference. The remaining subjects experienced difficulties unrelated to wireless phone interference due to severe hearing loss or excessive feedback. These results support the use of acoustic measurements of immunity as the basis for the ANSI C63.19 standard.
Ergonomics in the Dental Clinic
Authors: Proteau Rose-Ange
Published: January 2012

A number of dental hygienists have developed pathologies that cause them to be absent from work for long periods of time, and making it difficult for them to return to work. Hygienists' work involves extended static muscular effort in the neck and pectoral girdle, combined with recurrent dynamic movements of the wrist and fingers, associated with efforts to remove tartar from the teeth. Over the last two years, a dozen dental hygienists have consulted us for various shoulder, elbow, wrist, hand and finger problems. Changes in methods, instruments, equipment and the environment have allowed hygienists to adopt safer working positions. Reduced muscular activity was confirmed by EMG testing. The use of telescopic pivoting armrests has facilitated the adoption of new working methods by dental hygienists, and also provided needed arm support. A new concept for a pivoting armrest has been developed with round gel elbows-rests.
Analysis of Inappropriate Operating Posture for Dental Practice
Authors: Yoshihara Masaaki , Fujita Masahiro , Kawamoto Masayuki , Onchi Yoshimi , Kohmi Tadao , Fujii Benji , Inoue Masayoshi , Taniguchi Toshio
Published: January 2012

Dental treatment in the oral cavity where movement is restricted constrains dentists to many uncomfortable posture. We determined the most comfortable posture in the sitting position and compared them with the actual practical posture. The lengthened distance between the floor and the patient's oral cavity is thought to diminish the operator's physical stress.
Pushing and Pulling in Relation to Musculoskeletal Complaints
Authors: Hoozemans Marco J.M. , van der Beek Allard J. , Frings-Dresen Monique H.W.
Published: January 2012

The first cross-sectional analyses are presented of a longitudinal study regarding the relationship between pushing and pulling and musculoskeletal disorders. Workers exposed to pushing and pulling and workers who had administrative tasks received a questionnaire. A significant association between shoulder complaints in the past year and high exposure to pushing and pulling was found.
A Comparative Study of Accident and near Miss Reporting Systems in the German Nuclear Industry and the Norwgian Offshore Industry
Authors: Ringstad Arne Jarl , Szameitat Steffen
Published: January 2012

A basic assumption in modern safety management is that accidents are preventable through effective feedback control; i. e. through mechanisms by which information about accidents and near misses is utilised as a basis to increase the level of safety. In spite of their popularity, however, previous research has shown that it is frequently difficult to make Accident and Near Miss Analysis Systems (ANMAS) work according to intentions. The present paper presents results from a comparative study of ANMASs in the German nuclear industry and the Norwegian offshore industry. Both industries have a strong emphasis on incident recording and analysis. However, there are important differences between the two industries regarding what events are understood as “incidents”, what information on incidents is collected, how the information is processed, and how corrective actions are developed and implemented. These differences are analysed in light of distinctive features of the two industries (e.g. risk scenarios, technology, organisation), legislative factors, and social and cultural variables. It is argued that although different industry sectors may have a lot to learn from each other regarding how to handle accident and near miss reporting, the efficiency of a particular ANMAS must be evaluated relative to the industry's frame conditions.
Multimedia Training Systems for Education and Industry
Authors: Dahlke Grzegorz , Jasiak Aleksandra E.
Published: January 2012

The paper focuses on developing multimedia occupational safety and health training programs. The programs are designed for use in both the academia and the industry as modified methods of assessing occupational risk at workplaces are implemented in industrial companies.
Problems and Prospects of the International Code Council's Model Requirements for Building Design for Injury Prevention and Usability within the USA and Elsewhere
Authors: Pauls Jake
Published: January 2012

A major change in the way that model building codes and related model codes are developed in the USA, within the so-called International Code Council, has not been marked by a major improvement in code requirements that deal with problems of poor fit between design and user needs plus capabilities. Advocacy by the author, on both procedures and technical issues, has had mixed success especially in relation to stair and railing design and construction in homes. One response to this is a new public policy of the American Public Health Association which should help improve the potential for impact of public health professionals and ergonomists in the development of legally-enforced requirements for safety and usability of buildings.
Ergonomic, Biomechanical and Physiological Stresses from Manual Materials Handling in Grocery Distribution Centers
Authors: Garg Arun
Published: January 2012

Ergonomic, biomechanical and physiological stresses to the 63 male and 6 female wholesale grocery order sectors were studied in three different warehouses. The mean performance indexes were 119, 111 and 98% and the corresponding energy expenditures were 6.2, 6.0 and 8.3 Kcal/min and the average heart rates were 110, 122 and 133 beats/min. in warehouse 1, 2 and 3 respectively. The estimated compressive forces ranged from 411 to 658 kg on the male spine and 401 to 675 kg on female spine.
The Effectiveness of Physical Ability Testing in Preventing Industrial Injuries in Distribution and Logistics Operations
Authors: Anderson Charles K.
Published: January 2012

Physical ability testing can be effective in reducing the risk of injury in distribution and logistics operations. Job candidates who do not demonstrate the strength and aerobic capacity required to perform the job at the time of hire are at roughly double the risk of workers' compensation injury. Companies who have implemented physical ability testing have typically had a 20% to 40% reduction in injury rate from the year prior to implementation to the year after implementation.
An Aggressive Lift Training Program at a Grocery Distribution Center Yields Positive Results
Authors: Krost Mary
Published: January 2012

A highly customized lift training program, the Ergonomic Warehouse & Distribution Center Program, based on ergonomic principles and carried out at a large distribution center of a major retail organization as part of a broader safety program, yielded significant reductions in the center's accident frequency rate, especially with respect to musculoskeletal disorders. The program's positive results are attributed to its highly customized structure in both its content and in the participation of workers, supervisors, and safety department personnel.
High Levels of Behavioral Compliance in a Realistic Product Assembly Task
Authors: Kalsher Michael J. , Gallo Jason B. , Williams Kevin J. , Wogalter Michael S.
Published: January 2012

This study examined the effects of message framing on behavioral compliance in the context of a believable lab-based scenario designed to disguise the true purpose of the research. Participants were led to believe that the study's purpose was to improve the instructions that accompany consumer products requiring full or partial assembly and that they would perform a carpentry task that involved the use of several types of manual and power tools (e.g., a circular saw). The assembly instructions provided to them either did or did not contain a framing message. When it was present, the message was either framed positively (gain-frame) or negatively (loss-frame), or it merely instructed them to use personal protective equipment (PPEs) as directed by the on-product warning. An important outcome was the relatively high level of behavioral compliance observed. The message framing manipulation was not successful, but slightly higher levels of compliance were observed among participants in the loss-frame condition. Unexpectedly, level of experience (operating the circular saw) was positively related to compliance. This finding contrasts with the usual familiarity effects reported in other warnings research. Implications of this study for future research are discussed.
Careful Perusal of Reports on Slip, Trip and Fall Accidents Revealed the Need for Improved Orderliness at Workplaces
Authors: Kemmlert Kristina
Published: January 2012

Contributing factors to slips, trips and falls at work have been studied in 1.600 accident reports. Both older male and female workers had higher rates of reported STF accidents, but no significant gender or age differences were noted with regard to the factors contributing to the accidents. In the case of both men and women a lack of orderliness at the workplace was the most prevalent contributing factor to the accident. For a successful prevention of STF accidents, improved orderliness, better ladders, reliable safety devices and an effective snow clearance are needed together with a proper sense for the realism in initiated undertakings.
Slip Resistance – Adjusting to a New Paradigm
Authors: Bowman Richard
Published: January 2012

AS/NZS 4586–1999, Slip resistance classification of new pedestrian surface materials, rejects the concept that a universal minimum slip resistance threshold value is the arbiter of safety. Slip potential is a function of footwear, gait, test method, environment, etc. Test results may indicate the potential ‘contribution of the floor surface to the risk of slipping when wet’, but designers also have to consider the pedestrian contribution, the nature of the anticipated activity and the probable range of contamination conditions. What trust can be placed in individual test results, and what are the implications for forensic investigations? These questions are indirectly answered whilst also addressing more challenging fundamental issues.
Wear Progression of Shoe Heels during Slip Resistance Measurements
Authors: Kim In-Ju
Published: January 2012

Predicting changes in slip resistance performance with wear evolution is extremely difficult task and at present neither footwear nor flooring industries have a valid and reliable answer. Hence, in order to gain fundamental knowledge on wear mechanism, progressive wear and surface alteration processes of the shoes are investigated during repetitive dry rubbing. It is assumed that geometry changes of the shoe surface caused by wear development would be a major factor that affects the slip resistance performance. With the measurements of slip resistance, wear characteristics of two different shoes are comprehensively investigated based on the surface analyses and microscopic observations. For the systematic investigation of the surface alterations, topographic changes of each shoe were thoroughly examined on a regular time basis. The results show that surface alterations of each shoe were more severe than expected and occurred from the very early stage of sliding. It is also found that initially unstable friction process changed into the steady state friction process in the later stage of the slip resistance tests.
Perception of Slipperiness, Thermal Comfort and Wearability of Footwear used on Icy Surfaces
Authors: Gao Chuansi , Abeysekera John
Published: January 2012

The objectives of this study are to assess the perception of slipperiness, thermal comfort, and wearability of footwear used on icy surfaces, and the anti-slip effect of materials spread on ice using outdoor walking trials. Twenty-five subjects wore four types of footwear walking on five different icy surfaces. Five-point rating scale was used recording wearer's perception. The results showed that pure ice was perceived as very slippery. Spreading sand (180 g/m2) greatly decreased the slipperiness. Slip resistance, thermal insulation and wearability of footwear chosen were not properly integrated, and were ranked different in four types of footwear. In addition to thermal insulation, prevention of slip and fall hazard by improving anti-slip property and wearability must also be priorities for development of footwear for use in cold climate.
Global Standardization of Human Factors for Medical Devices and Systems
Authors: Wiklund Michael E. , Carstensen Peter B. , Weinger Matthew B.
Published: January 2012

This panel addresses current domestic and international standards for medical devices and systems in Latin America, Europe, Asia, Canada and the United States. Following a presentation of current standards development efforts, there will be an open discussion of HF standard overlaps and conflicts, opportunities for harmonization, and additional areas of need. Time permitting, the value of technical standards versus performance standards as a means to reduce the probability of use error involving medical devices and systems will be discussed.
Misadventures of Medical Labeling: Lessons Learned
Authors: Callan James R. , Kobus David A.
Published: January 2012

Medical errors are increasingly being brought to the attention of the public through articles and reports that cite cases of patient death or injury through errors in doseage, misuse of medical devices, or procedural error. The incidence of such errors is extremely high. Over 180,000 deaths per year have been attributed to medical error, the equivalent of the loss of a 747 aircraft load of passengers every day of the year. Most of these errors are preventable and may be the primary health care problem in the U.S. today. The authors present a selection of case studies of error in medical treatment, with particular attention to those that can be related to, or that have implications for, medical device and drug labeling. Cases will be highlighted that could have been avoided had good human factors practices been followed. In contrast to much of the recent emphasis on blaming clinical personnel for medical errors, it is suggested that adoption of existing human factors engineering guidelines for both labeling and device design can have a significant, positive effect on this serious, societal problem.
Medical Device Alarms: Equipment-Or Patient-Centered?
Authors: Edworthy Judy
Published: January 2012

Medical device alarms are in a continual state of development in the sense that manufacturers are always upgrading and updating equipment, a process that is usually accompanied by the updating and enhancement of alarm systems. This updating can lead to confusion and overload for the operator. However, by changing the focus from the equipment and its associated alarms to the patient, and the physiology of the patient, these problems could be substantially reduced. This paper argues the case for making these alarms patient- rather than equipment-centered, and proposes also that the method for generating ideas about the nature of these alarms should also be determined using user-centered techniques.
Hand Tools Design: Are Biomechanical Criteria the Same as Aesthetic Criteria? a Preliminary Study
Authors: Christensen Adam D. , Bishu Ram R.
Published: January 2012

The perception of comfort and discomfort was investigated using a tactile knife-handle sorting task. Sixteen participants (13 males, 3 females) volunteered to perform the study. Due to the preliminary nature of this research the participants were acquaintances of the researchers. The participants were randomly assigned to sorting condition of either Comfort or Discomfort. Multidimensional scaling (MDS) was utilized to examine the structural perceptual equivalence of comfort/discomfort conditions on the sorting task. Results indicate that there is little difference in dimensional solutions for comfort versus discomfort, furthermore post hoc inspection of the dimensions and stimuli suggest the participants are using handle length (Dim 1), handle circumference (Dim 2), and surface texture (Dim 3) to group the knife handles. Support for a more in-depth study of comfort/discomfort incorporating attribute ratings and implications for designers are discussed.
Comparative Analysis of Functional Wrist Brace and Wrist Angle on Maximal Grasp Strength
Authors: Nguyen P. T. , Cherry J. , Jung M. C. , Marieneau R. , Hallbeck M. S.
Published: January 2012

Wrist braces have been used in the industry with the notion that they would restrict the range of motion of the wrist to an extent that it would decrease the risk of CTS during forceful repetitive tasks and enhance productivity. The purpose of this study was to evaluate the effects of the functional wrist brace, wrist angle, and fatigue on maximal grasp strength. Fourteen male and sixteen female college students participated in the study utilizing a soft brace, a hard brace, and no brace in three different static wrist positions (45° flexion, neutral, and 45° extension) prior to and after fatigue to determine the effect on maximal grasp strength measured by a computerized wrist dynamometer. The results of the ANOVA indicated that grasp strength was significantly greater when the wrist was in the flexion position followed by neutral, then wrist extension. However, brace type and fatigue states did not produce statistically significantly different grasp strengths overall. Therefore, the position a grasping task is performed at should be evaluated keeping in mind that the neutral and flexion positions allow for the greatest maximal grasp force with or without a wrist brace. Wrist braces are not recommended as a preventative or protective device during forceful repetitive tasks but the effects of their usage on maximal grasp strength must be evaluated with special consideration of the post-fatigue state.
When do Bending Stresses on the Spine Rise to Damaging Levels?
Authors: Dolan Patricia , Adams Michael A.
Published: January 2012

Experiments on cadaver spines have quantified the bending stresses (bending moment) required to cause overload injury or fatigue failure to the lumbar spine. This paper reviews subsequent experiments in living people which sought to identify the circumstances that cause spinal bending to rise to potentially damaging levels in life. Healthy volunteers performed various bending and lifting activities in the laboratory, and peak bending moment was quantified from measurements of lumbar flexion, obtained using the 3-Space Isotrak. Bending stresses approached or even exceeded estimated fatigue limits in some subjects when they performed lifting tasks in the early morning (when the spine's bending stiffness is increased), and following fatigue of the back muscles. Individuals with a small range of lumbar flexion were particularly likely to exceed safe limits. These findings may explain why repeated bending and lifting are so closely associated with low back problems.
Effect of Center of Mass and Handle Location of Two-Wheeled Refuse Containers on Mechanical Loading
Authors: Kingma Idsart , Kuijer P. Paul F.M. , Hoozemans Marco J.M. , Van Dieën Jaap H. , Van Der Beek Allard J. , Van Der Frings-Dresen Monique H.W.
Published: January 2012

The aim of the current study was to find out how the center of mass (COM) and handle location of a two-wheeled container affects handle forces and joint loading. Forces at the handles and joint loading were quantified in four subjects during steady, two-handed pushing and pulling of two-wheeled containers with nine different COM locations and eleven different handle locations. The COM location turned out to have a major influence on handle forces and joint loading, whereas the influence of the handle location was moderate. Subjects considerably adapted the tilt angle of the container in response to variations in handle location but hardly in response to variations in COM location. For two-handed pushing and pulling the current design of a two-wheeled container can be improved by moving the centre of mass of the loaded container in the direction of the axis of the wheels and by slightly increasing the height of the handles.
Occupational Safety and Health: A Cross-Cultural Comparison
Authors: Luczak Holger , Kumashiro Masaharu
Published: January 2012

Occupational safety and health (OSH) is of varying importance in the different countries of the world with different cultural traditions, status of general technology and so forth. Hence, the OSH systems vary from country to country. In this multi session symposium the state of OSH will be analyzed: What are the strategies and changes in the different countries? Are there specific regional distinctions, how did regions cope with specific changes? What strategies and actions are employed at the company level?
International Comparison of Osh Research
Authors: Luczak Holger , Rötting Matthias , Brüggmann Matthias
Published: January 2012

The comparison of occupational safety and health (OSH) systems can be done with many different focuses. First, a definition of “occupational safety and health” is needed. Such a definition is by no means universal, in different cultures, countries and times OSH had different meaning. Based on a broad definition of OSH, a corresponding criteria system will be presented that can guide further analysis. An analysis of OSH research will be given with respect to the methods used, the focuses of research, the legal regulations and the industrial relations in different cultures and countries and different times.
High Risks of High Backrests
Authors: Van Veelen Martine A. , Van Goossens Richard H.M. , Van Chang Annemarie , Van Kumar Shrawan , Van Snijders Chris. J.
Published: January 2012

When designing office chairs and wheelchairs, most attention is paid to geometry to adjust chairs to individual body dimensions. The aim of this study is to gain insight in biomechanical sound design criteria for the backrest. Out of a biomechanical model and tests on a healthy population it was concluded that free shoulder space of at least 6 cm is needed when designing a backrest for a wheelchair. And when focussing at the inclination of the backrest, an opening angle between seat and backrest of 90° degrees is wanted.
Decubitus Risk: Is Shear More Important than Pressure?
Authors: Goossens Richard H.M. , Pas Martijn A. , Teeuw Robin , Snijders Chris. J.
Published: January 2012

A mechanical load through which the capillaries are closed causes tissue ischaemia of the skin. Most authors agree that it is this tissue ischaemia that is the main factor in the cause of pressure sores. Different combinations of mechanical load on the skin may have the same effect within the skin. The aim of this study is to evaluate the effect that different combinations of pressure and shear have on blood flow within the skin. The skin blood flow was measured by means of skin oxygen tension. Different load combinations on the skin surface, for which the maximum shear stress within the skin remained equal, showed no significant difference in skin blood flow. Research should therefore focus on load situations within the skin instead of pressure measurements on the skin surface only.
An International Thermal Comfort Standard for People with Special Requirements
Authors: Parsons K C
Published: January 2012

The International Standards Organisation (ISO) is currently working on a project to produce an international standard entitled; “Ergonomics of the Thermal Environment: application of international standards for people with special requirements”. Progress has led to a draft of the standard that will be considered for international voting and comment. Eventually, with acceptance, ISO 14415 will be published in full standard or technical report form. The work recognises that people with physical disabilities may have special requirements in terms of what are appropriate thermal environments and that current international standards may not apply or would need to be modified. Examples include standards for the estimation of clothing insulation and metabolic heat production. There may also be modifications to methods of assessment such as those given in thermal comfort standards. This paper describes the development of the standard and its current form. It also provides a discussion of possible improvements to the standard including a new approach based upon adaptive and behavioural assessment methods.
Vision and Body, Integrated Systems in Systemic Interplay
Authors: Fostervold Knut Inge
Published: January 2012

Based on an ecological analysis of the visual system, a systemic model is proposed linking visual stress and symptoms in other parts of the body. The model links the interaction between the oculomotor system and other body muscles to the slow-acting mechanism of Scohr's two-step theory of vergence control. Implications of the model have been examined in a field study. The results indicate that increased closeness between natural near work and VDU-work yield reduced symptomatology not only for eye symptoms but also for visually related symptoms in a broader sense.
Muscle Activity during Securings with Pneumatic Nutrunners
Authors: Forsman Mikael , Cyrén Henrik , Möller Therese , Kadefors Roland , Mathiassen Svend Erik
Published: January 2012

Musculoskeletal disorders are common among workers who use powered hand held tools in assembly industry. The present study was carried out at a bus assembly plant where pneumatic nutrunners are the dominant powered hand tool. The activity in five muscles was measured for different phases of the securing, comparing soft and stiff joints, three different joint positions, and two powered tools. The aims were to characterize the muscular load during usage of the chosen tools, and to be able to provide relevant information to the production engineers, who were to design a new production system. The variance in muscular activity was large, both within subjects and between the mean curves of different subjects. Still, it was possible to obtain characteristic shapes of EMG curves sampled under different conditions. EMG peaks were seen in the hand extensor muscles for the right-angled tool. Joint position strongly contributed to differences in muscular activity in all muscles, which together with the finding that the tools made very small differences, were regarded as the most valuable results for the production engineers.
Electromyographic and Discomfort Analysis of a Confined-Space Welding Task
Authors: Lowe Brian , Wurzelbacher Steven , Shulman Stanley , Hudock Stephen
Published: January 2012

Welders have been reported to experience musculoskeletal symptoms and pain in the shoulder, neck, and low back regions (Torner et al., 1991). Welding occupations involve prolonged static exertions with awkward postural stresses that may be exacerbated in confined spaces. This study examined a specific welding job at a shipyard where confined-space welding operations are prevalent. The process under investigation in this study requires the welders to weld the seams on the inside of “honeycombs” which form the underside of vessels. These honeycombs are approximately 0.61 m (width) x 0.61 m (height) x 4.88 m (length). Welding trials were conducted in a mock-up of this confined space with nine employee volunteers from the shipyard. Subjects welded a 1-m bead along the bottom corner of the honeycomb on the right followed by the left side, with each weld taking two to three minutes to complete. Subjective reports of regional discomfort and an overall general discomfort rating were obtained immediately following each trial. Surface electromyography (SEMG) was recorded from seven muscle groups on the welders' dominant hand side: trapezius, middle deltoid, anterior deltoid, latissimus dorsi, erector spinae, FDS, and EDC. The percent of the total SEMG spectral power in the 10–30 Hz frequency band was calculated by Fast Fourier Transform for each 1-s sample of SEMG from each muscle. A two-minute time series, extracted from the beginning of the welding trial, was partitioned into five, 24-s segments for which the percent of the total spectral power in the 10–30 Hz frequency band (PP10–30) was averaged over 24 seconds. Shifts in the average PP10–30 were examined over the five segments. The hypothesis was that the use of a wire-fed welding process (FCAW) would result in less fatigue than a stick electrode welding process (SMAW). This hypothesis was generally supported as, for most muscles, the stick electrode welding process was associated with higher percentage increases in the average PP10–30 than the wire-fed welding process (p < 0.05). However, regional discomfort scores were not significantly affected by weld process. While the subjectively reported discomfort was generally low for both welding processes, the SEMG results show some evidence that the wire welding process may be preferable in terms of a reduction of muscle fatigue. This shipyard is considering implementing the wire-fed welding process to replace the traditional stick welding process.
Changes in Physiological Parameters for the Saudi Males during Physical Exercises
Authors: Jomoah Ibrahim M.
Published: January 2012

The main objective of this study was to assess the physiological capabilities of Saudis through the following: (1) measuring and evaluating some physiological parameters (heart rate, body temperature, blood pressure) for Saudis involved in light, moderate and heavy exercises; and (2) studying the changes in patterns of the measured parameters in the three phases of exercises: resting, during exercise, and recovery.
Perception of Surface Pressure Applied to the Hand
Authors: Johansson Lena , Kjellberg Anders , Kilbom Åsa , Hägg Göran M
Published: January 2012

The aim of the study was to determine the relationship between the physical magnitude and the subjective perception of applied pressure, and to determine discomfort and pain thresholds. Free modulus magnitude estimation of the subjective pressure level was made on three points: on the finger, the palm and the thenar area. The pressure was rated higher at the thenar point than at the finger and palm points. The slope of the linear functions ( log ratings as a function of log pressure) was 0.66, 0.78 and 0.76 for the finger, palm and thenar points respectively. The discomfort threshold was 38 % of the pain pressure threshold at the finger point, 40 % at the palm and 22 % at the thenar point.

The results are probably of importance in the performance of handintensive work, in particular in the design of hand tools.
Using MVTA to Assess Upper-Extremity MSD Risk and Performance in a Retail Environment
Authors: Lehman Katherine R. , Ryan Mary M. , Psihogios Jennie
Published: January 2012

The Multi-Media Video Task Analysis (MVTA) tool was utilized in a retail environment to assess upper-extremity motion of cashiers. The objective of this study was to quantify wrist motion in order to evaluate the ergonomic impact of a new piece of technology on the upper-extremities. Data were collected before installation of a magnetic-based security system and four months after cashiers had been trained and used the new system in their jobs. Both video and wrist motion, collected via electro-goniometers, were captured from six cashiers processing customer transactions in a Dutch supermarket. MVTA allowed the analysts to demarcate precise sub-tasks of the demagnetizing and scanning process and link corresponding wrist posture and acceleration which allowed for a more powerful assessment. Task and workstation design recommendations were made to reduce extreme wrist postures. In addition, task time differences between the current and new systems were assessed to ensure that the change would not negatively impact performance.