| 51. |
|
|
| 52. |
- Mazaheri, Ava, et al.
(författare)
-
Reaction force exposure for tightening tool users : A psychophysical based experimental study of electric right-angle nutrunners
- 2022
-
Ingår i: Applied Ergonomics. - : Elsevier BV. - 0003-6870 .- 1872-9126. ; 103
-
Tidskriftsartikel (refereegranskat)abstract
- Reaction forces from nutrunner tools constitute a risk of developing MSDs. However, recommendations for sustainable reaction force levels are lacking. The aim of this study was to inform recommendations regarding reaction load exposures from right-angle nutrunners. Through a psychophysics approach, experienced assembly workers subjectively assessed reaction loads when using a nutrunner in six combinations of tool tightening strategy, work-pace and screw-joint stiffness. Electromyography, tool and joint parameters were measured. Regardless of tightening strategy, joint stiffness and work-pace combinations, no large differences in acceptable tightening torque, peak reaction force, and handle displacement were observed. However, acceptable jerk and impulse differed substantially between the TurboTight (R) (high-acceleration) and QuickStep (R) (conventional) tightening strategies. Although the TurboTight (R) strategy overall showed reduced peak muscular activities compared to the QuickStep (R), the participant-rated acceptable torque levels were similar, plausibly due to TurboTights' high jerk levels. Jerk and impulse are hypothesized to influence the perception of reaction loads.
|
|
| 53. |
|
|
| 54. |
- Mazaheri, Ava, et al.
(författare)
-
Reaction load exposure from handheld powered tightening tools : A scoping review
- 2021
-
Ingår i: International Journal of Industrial Ergonomics. - : Elsevier BV. - 0169-8141 .- 1872-8219. ; 81
-
Tidskriftsartikel (refereegranskat)abstract
- Assembly workers using handheld powered tightening tools are repetitively subjected to reaction loads resulting from the tool handle. Despite the vast amount of research, tool manufacturers and OSH practitioners still lack well-grounded recommendations and benchmarks for ergonomics evaluations of reaction loads. This review provides an overview of research investigating reaction loads and operator physical demand, and identifies gaps in current means of evaluating reaction load exposure from tightening tools. A scoping review was conducted, scanning for quantifications of reaction loads as well as reported indications of MSD risks following tightening tool use. Suggested maximum exposures for reaction loads were further identified. The most commonly investigated quantities among the 40 publications included, were peak reaction force/torque (70%) and handle displacement (70%), followed by impulse (23%). Pneumatic tools were studied at greater extent (65%) than electric tools (30%). Three studies presented a relationship between reaction load exposure and physiological changes, i.e. edema, tissue oxygenation and blood volume changes, indicating an elevated risk of developing MSDs. Four publications proposed values for maximum reaction load exposure, expressed as either reaction torque, handle displacement, or tightening torque. To conclude, strategies for developing recommendations for reaction load exposure are suggested. Less investigated reaction parameters, e.g. impulse, can carry additional relevant information regarding exposure. Exposure values should be expressed as physical quantities of the reaction load rather than tightening torque. Recommendations are further needed for various tool handle-configurations, emphasizing the increasingly used electric tools. Such recommendations can eventually contribute to reducing MSDs resulting from tightening tool use.
|
|
| 55. |
- Mazaheri, Ava, et al.
(författare)
-
Reaction Parameters Linked to Cumulative Trauma Disorders during Use of Powered Tightening Tools : A Literature Review
- 2019
-
Ingår i: PREMUS 2019. 10th International Scientific Conference on the Prevention of Work-Related Musculoskeletal Disorders.. ; , s. 255-
-
Konferensbidrag (refereegranskat)abstract
- Background: The impact of physical reactions on human operators generated byhandheld powered tightening tools has been researched by evaluating variousparameters, here referred to as ‘reaction parameters’. The objective of this literaturereview is to investigate which reaction parameters commonly are assessed duringphysical load evaluations of tightening tools, as well as reported correlations betweenreaction parameters and risk of developing cumulative trauma disorders (CTDs). Anadditional aim is to map exposure limits established for reaction parameters and identifyknowledge gaps regarding tightening tool impact on operators, if any.Methods: A systematic approach was adopted to review relevant literature, followingthe PRISMA flow-diagram. Synonyms of defined keywords were combined for search in3 databases. 76 articles were read and evaluated against inclusion criteria, of which 47articles where included in a qualitative synthesis. An overview of the assessed reactionparameters was obtained, as well as suggested linkages between these parameters andrisk of injury development.Results: Main parameters studied in literature are reaction force/torque (79%) andhandle displacement (74%). Impulse and handle velocity are studied in 26% and 15% ofthe articles, respectively. 51% of the studies also report a correlation between assessedreaction parameters and risk of developing CTDs. Three studies present exposure limitsfor reaction parameters. 1/3 of the studies were conducted on electric tools, whereasapproximately 2/3 were performed on pneumatic tools.Conclusions: There is a knowledge gap concerning several reaction parametersand their implications for developing CTDs, especially regarding impulse, tool handlevelocity/acceleration and grip force. Their influence is suggested to be explored infurther studies. Establishing exposure limits related to the reaction parameters wouldtranslate the scientific knowledge into industrially applicable recommendations. Further,the need for studies on electric tools is evident, due to a shift in the industry frompneumatic to electric tools.
|
|
| 56. |
- Middeldorp, Christel M., et al.
(författare)
-
The Early Growth Genetics (EGG) and EArly Genetics and Lifecourse Epidemiology (EAGLE) consortia : design, results and future prospects
- 2019
-
Ingår i: European Journal of Epidemiology. - : Springer Science and Business Media LLC. - 0393-2990 .- 1573-7284. ; 34:3, s. 279-300
-
Tidskriftsartikel (refereegranskat)abstract
- The impact of many unfavorable childhood traits or diseases, such as low birth weight and mental disorders, is not limited to childhood and adolescence, as they are also associated with poor outcomes in adulthood, such as cardiovascular disease. Insight into the genetic etiology of childhood and adolescent traits and disorders may therefore provide new perspectives, not only on how to improve wellbeing during childhood, but also how to prevent later adverse outcomes. To achieve the sample sizes required for genetic research, the Early Growth Genetics (EGG) and EArly Genetics and Lifecourse Epidemiology (EAGLE) consortia were established. The majority of the participating cohorts are longitudinal population-based samples, but other cohorts with data on early childhood phenotypes are also involved. Cohorts often have a broad focus and collect(ed) data on various somatic and psychiatric traits as well as environmental factors. Genetic variants have been successfully identified for multiple traits, for example, birth weight, atopic dermatitis, childhood BMI, allergic sensitization, and pubertal growth. Furthermore, the results have shown that genetic factors also partly underlie the association with adult traits. As sample sizes are still increasing, it is expected that future analyses will identify additional variants. This, in combination with the development of innovative statistical methods, will provide detailed insight on the mechanisms underlying the transition from childhood to adult disorders. Both consortia welcome new collaborations. Policies and contact details are available from the corresponding authors of this manuscript and/or the consortium websites.
|
|
| 57. |
- Neumann, W. Patrick, et al.
(författare)
-
A comparison of work-rest models using a "breakpoint" analysis raises questions
- 2020
-
Ingår i: IISE TRANSACTIONS ON OCCUPATIONAL ERGONOMICS & HUMAN FACTORS. - : Informa UK Limited. - 2472-5838 .- 2472-5846. ; 8:4, s. 187-194
-
Tidskriftsartikel (refereegranskat)abstract
- OCCUPATIONAL APPLICATIONS Designing sustainable cyclic work requires attention to both the workload amplitude as well as the duty cycle, the fraction of the work cycle with active workload, that therefore also defines the recovery phase of the cycle. A number of different approaches and models have been developed to calculate the required recovery time for a given load and duty cycle. We present a comparison of three types of models at the "breakpoint" that defines the boundary of load amplitude and duty cycle where fatigue begins to accumulate faster than recovery allows within the work cycle. This comparison shows considerable variation between models of the "allowable" load or duty cycle depending on the method used. Practitioners should thus be cautious applying these models indiscriminately in job design as their results can vary substantially. In particular, differences between the tasks used for model formulation and application may compromise validity, and model application in a given context should be verified before broad application. TECHNICAL ABSTRACT Rationale: There is a need for tools to help design sustainable work in which muscular capacity and other human resources can recover at least as quickly as they are used. Purpose: In this brief report, three different approaches presented in the literature to determining work-rest schedules in cyclic work are compared. Methods: First, a set of five different muscular endurance models coupled with a recovery time model were considered, both with and without a dynamic work correction factor. Second, we examined a model of "resumption time", and third a psychophysically-based model of maximum duty cycle was included. These models were compared using the concept of a "breakpoint" in fatigue accumulation-the point at which a given load amplitude and duty cycle combination begins to cause accumulation of fatigue in each cycle and from which there is inadequate time to recover. Results: While the five endurance time models all behaved similarly, both with and without the static-to-dynamic correction factor applied, the three different types of modeling approaches provided substantially different response patterns. The psychophysically based model provided the most protective guideline among the models compared. Conclusion: These models should be applied with caution to particular work scenarios. Further research is needed to test accuracy and effectiveness when applying such models to a range of task scenarios to establish safe workloads and loading times in the design of repetitive work.
|
|
| 58. |
- Nilsson, Birgitta, et al.
(författare)
-
Förbättrad arbetsmiljö för anläggningsmaskinförare
- 2004
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Denna rapport sammanfattar resultatet av projektet ”Analys av personskaderisker och deras kostnader för företag med anläggningsmaskiner”. Det har genomförts på uppdrag av Prevent i samarbete med Maskinentreprenörerna (ME), Svenska Byggnadsarbetareförbundet (Byggnads) och Facket för Service och Kommunikation (SEKO) och har finansierats av AFA. Syftet med projektet har varit att i) få en översikt av personskadorna (arbetsolycksfall och arbetssjukdomar) och deras kostnader för företag och ii) systematiskt identifiera och bedöma riskerna med arbete i maskinerna och de kostnader de medför för företagen samt iii) undersöka och föreslå risksänkande åtgärder samt skatta riskerna och kostnaderna om dessa åtgärder genomförs. Resultaten baseras främst på arbetsplatsanalyser, intervjuer med maskinförare och företagsledare, litteraturstudier, statistikbearbetningar och analyser med riskhanteringsmetoderna SCA och MAWRIC. Resultaten visar att anläggningsmaskinförare har en påfrestande arbetsmiljö. Belastningsskada är den vanligaste och allvarligaste arbetssjukdomen och den vanligaste arbetsolyckan är att skada sig vid i- och urstigning (fallolyckor). Risken att skada andra runt maskinen upplevs som påfrestande och det sker såväl tillbud som olyckor där människor runt maskinen skadas. Ett viktigt resultat i projektet är en sammanställning av förslag på hur man kan minska personskaderiskerna, både genom att använda redan befintliga lösningar och genom att utveckla nya. Såväl organisatoriska som tekniska förändringar föreslås. Resultaten med SCA visar att de arbetsrelaterade personskaderiskerna medför kostnader för företaget som är i storleksordningen en tredjedel av företagets vinst. Detta är en väsentlig del av företagets resultat. MAWRIC-analysen visar att det finns möjligheter att förbättra arbetsmiljön och att sådana förbättringar bör minska personskaderiskerna. Investeringarna är kostsamma, men medför såväl färre skador som ekonomiska besparingar på sikt (här sett på en femårs-period). Kostnaderna för personskador skulle minska till att därefter utgöra motsvarande 1/8 av vinsten. Detta är en avsevärd sänkning. Förhoppningen är att företag och branschen drar nytta av resultatet från studien och inspireras till arbete med att förbättra arbetsmiljön. Det tjänar alla inblandade på.
|
|
| 59. |
|
|
| 60. |
- Nilsson, Birgitta, et al.
(författare)
-
Packaging Ergonomics
- 2005. - 1
-
Ingår i: The Ljungberg Textbook. - Stockholm : KTH.
-
Bokkapitel (populärvet., debatt m.m.)
|
|
