Ergonomics of Bus Driver Seat - Literature review Example

ERGONOMICS BUS DRIVER SEAT Introduction In the modern industrial and service operations environment, people perform different tasks that require sensory and cognitive as well as physical capabilities to effectively accomplish numerous tasks that would drive economic activity. Therefore, human performance should be examined taking into account anatomic, physiological, psychological and industrial aspects of the work people do. For that purpose, ergonomics as a study is useful as it enables researchers to understand the natural laws of human performance, their interaction with the products, systems and processes. The emphasis is put on the design of the strengths and abilities of people and minimization of the effects that limit human performance. The following paper will examine the concept of ergonomics; will also apply ergonomics toward analyzing such product as a bus driver seat. The paper will define possible changes to be implemented to improve the ergonomics of bus driver seat and will conduct a comparison analysis of ergonomics and design of an old and new bus driver seat. History of ergonomics There is a consideration that early indications of ergonomics were attributed to the physician Ramazzini, the founder of the occupational medicine, who related a wide variety of common workers’ diseases to be the result of prolonged and irregular motions during the performance of certain task (Lehto & Landry, 2012). Later developed by Taylor, ergonomics in the modern world has fewer relations to the working conditions than it had at the time of Taylor’s studies, however, the followers of those studies contributed largely to the management theory and provided the basis for applied ergonomics and human factors. As a study of human performance and its application to the design of technological systems, ergonomics includes human-computer interface issues, environmental and work design, and also physical and mental workload assessment. As a discipline, ergonomics is classified into such domains as physical, cognitive and organizational, the aim of which is to guide the assessing risk factors and reducing of the influence of different issues on workers in the occupational environment (McCauley-Bush, 2011). The lack of normal functioning of human body caused appearance of different injuries, such as carpal syndrome and tendonitis. In the modern world, these diseases are connected with the excessive repetition, force and excessive joint deviation during the performance of certain tasks (Lehto & Landry, 2012). Critical ergonomic analysis of bus driver seat While the contributing disciplines in ergonomics include physiology that provide an understanding about how the physical aspects of the human respond to the work environment. If to take an example of the bus drive seat, there have been conducted a lot of studies on the occupational health of bus drivers (Kompier, 1996). Disorders of muscle-skeletal function are a main health problem related to work of bus drivers, with the frequent complaints on the lower and upper parts of the back, neck, shoulders and knees. There is the high level of vibration and the forced seating position, which cause trouble with sitting and working in an uncomfortable body posture. Hence, examining of driver’s seat should be conducted in order to make it more efficient for the work. Jonsson, Rynell, Hagberg and Johnson (2014) state there is an essential factor in bus and seat design for the bus driver’s whole-body vibration. The European Union directive has already developed the limitation to the use of whole-body vibration, specifying the daily exposure action values and the daily exposure limit values. Whether the daily exposure action values are exceeded, the directive recommends the drivers to reduce the use of whole-body vibration. It has also established the modified driver seat, which should be at a good viewing height and in normal distance from the steering wheel and the pedal. The driver seat should be adjusted to body shape, should be with lateral support for good sitting stability, should have the armrest, lengthening of sliding drivers’ seat and have the adjustable seat-belt (Directive 2006/126/ec of the European Parliament and of the Council, 2006). During the study described by Jonsson, Rynell, Hagberg and Johnson (2014), the two seat types were evaluated, the one of which was the air-suspension or height adjustable that enable the drivers to reduce the vibrations transmitted to the seat. The other type of seat evaluated was the pedestal seat that contained gas spring in the seat base when the driver wanted to adjust the height. The main shock absorption came from the foam in the seat pans. Lee and Gak (2014) have examined the role of physical and chemical risk factors on the vibration and exhaust emissions of bus drivers. They pay attention on the fatigue caused by the driving and that question should be more examined due to the fact that bus drivers are responsible for their and passengers’ safety, hence, their health conditions are vital. The results of the study conducted (Lee & Gak, 2014) evidence about the lack of education about the proper driving posture and ability of self-stretching methods. The bus driver’s seat improper design created uncomfortable position for the driver, which cause the inappropriate working conditions for the driver. Alperovitch-Najenson et al. (2010) also argue about the ergonomic and occupational and psychological risk factors connected with the uncomfortable bus drivers’ seat. Such seats were associated with the higher level of lower back pain among the bud drivers. While their awkward body postures lasted for the extensive periods during the work, such as slumped sitting, leaning on one side, bending and excessive reaching, bus drivers were at risk in obtaining mechanical stress upon the spine and the surrounding of their work place. Kovacevic, Vucinic, Kirin and Pejnovic (2010) also state about the negative consequence of the inappropriate adjusted driver’s seat. They state that as the driver’s seat is adjusted to average anthropometric measurements of the human body, individuals who do not fit these measurements, can have certain difficulties when driving a car. Thus, depending on the driver’s height, there can be problems with reaching controls or lack of space. However, through appropriate correction of seat shift, the problem can be solved partially. Possible changes to be implemented to improve the ergonomics of bus driver seat The most important recommendations concerning the design and construction of the drivers seat are to ensure that it will be adjustable to every driver despite the height in order to obtain comfortable driving postures (Tse, Flin & Mearns, 2006). It is also recommended the range of adjustments of many seats to be enlarged; adjust the springs the lumbar support w in height and thickness; provide easy-to-operate controls for adjustability to all the drivers. Lee & Gak, 2014 consider the working environment of bus drivers can be improved through adopting regular resting times and places for recovery of drivers’ fatigue. Moreover, a driver’s seat can be fixed with a neck support that would support the cervical vertebrae in order to improve the bus drivers’ musculoskeletal symptoms. In addition, the armrests will reduce muscle tension around the shoulder joints and will improve the overall driving posture. The bus drivers should be educated to avoid greater than 90° of hip extension and greater than 60° of knee flexion as well. ISO Focus (2014) have already adopted a Technical Specification that describes which direction to move a hand control to upshift or downshift through gears without a need for a clutch pedal in a manual transmission. The other initiative specified the design of the workplace of the bus drivers with the attention on four parts of the standard that address the driver cabin dimensions, vision, information and control devices and cabin environment. ISO Focus and its working groups have also developed standards that meet the measurement methods for seats and pedals. Thus, Schlosser (2007) states that school bus manufacturers improve ergonomics of driver compartments from steering wheel positioning to air ride seats. They find adjustability as the key to comfort of the bus drivers. Air ride seats are also the most favored ergonomic improvement. Comparison of ergonomics and design of an old and new bus driver seat Rupp (2014) states that there were no considerable changes in the ergonomics of drivers and vehicle. However, there are certain new technologies that are implemented into the automobile industry and thus concern the ergonomics of the driver seat. While the field of automotive ergonomics in the 1960s focused on the development of vehicle architecture, the physical side of ergonomics, its tools and methods, pedals, seat, steering wheel were paid additional attention The workspace of the driver was refined and the new studies enabled to provide drivers with the right positioning of the different elements in a vehicle. Now the seats are designed the way they provide the durable comfort for the driver and a fully integrated three-point seat belt system. Schlosser (2007) reports that in the current time, bus manufacturers are working on meeting the drivers’ ergonomic needs. Steering wheels have changed with the standardized sizes, rom the larger to the smaller. Telescoping feature in the steering wheel is used to better accommodate for height of driver, there is a new pedal placement and adjustability, which makes the pedals movable in a safer way, as they are easier to reach for drivers of different height. There is also a need in the future studies and research in order to concentrate on knowledge improvement of the exposure–response relationship between whole-body vibration and the occurrence of low back disorders among the bus drivers. Moreover, there is a need to make optimization of the lumped parameter models with required complexity. The seat design should be also examined further for reduction of human vibration that comes from the interaction between road and a bus. Conclusion There are many benefits of ergonomically comfortable seats for bus drivers. One of the most important features is the impact of well-adjustable seat to the job efficiency and safety of the bus driver. If drivers’ seats are designed to meet their ergonomic needs, they will be able to work for longer periods of time and there will be less harmful impact on their health. Hence, without an adequate ergonomic setup, bus drivers are vulnerable to wide variety of serious health diseases which in turn can cause unsafe situations on the road. While the driver’s station, especially if that is a bus, can be used by different drivers, there appears a certain challenge of creating a seat that would be designed for people of different anthropometrical data. If the seats are designed in accordance to the ISO standards and correspond these anthropometric characteristics, the drivers will feel comfortable while working. However, with the capabilities of the modern industries, modern bud drivers’ seats are created with the modular design that reduces the complexity of the repair work; they have also an innovative pneumatic support that also maintains preventive posture. References Alperovitch-Najenson et al., (2010). Low Back Pain among Professional Bus Drivers Ergonomic and Occupational-Psychosocial Risk Factors, Israeli Medical Association, Vol.12 Directive 2006/126/ec of the European Parliament and of the Council, (2006). Official Journal of the European Union, L 403/19 Jonsson, P., Rynell, P., Hagberg, M. and Johnson, P., (2014): Comparison of whole-body vibration exposures in buses: effects and interactions of bus and seat design, Ergonomics Rupp, G., (2014). Ergonomics in the driving seat, ISO Focus Kompier, M., (1996). Bus drivers: occupational stress and stress prevention, International Labor Organization Kovacevic, S., Vucinic, J., Kirin, S. and Pejnovic, N., (2010). Impact of anthropometric measurements on ergonomic driver posture and safety, Periodicum Biologorum, Vol. 112, No 1, 51–54. Lee, J. and Gak, H., (2014). Effects of Self Stretching on Pain and Musculoskeletal Symptom of Bus Drivers, US National Library of Medicine National Institutes of Health, Vol.26(12) Lehto, M. and Landry, S., (2012). Introduction to Human Factors and Ergonomics for Engineers, 2nd ed. CRC Press McCauley-Bush, P., (2011). Ergonomics: Foundational Principles, Applications, and Technologies, CRC Press Schlosser, N., (2007). Drivers Respond to Key Ergonomic Changes, Schoolbusfleet, Retrieved from http://www.schoolbusfleet.com/channel/management-training/articles/2007/11/drivers-respond-to-key-ergonomic-changes.aspx Tse, J., Flin, R. and Mearns, K., (2006). Bus driver well-being review: 50 years of research, Transportation Research Part F 9, 89–114, Elsevier Ltd. Read More