It is worth to think about the potential ergonomic problems that might occur in the work place and plan ahead to avoid them, rather than waiting for them to occur and waist the time trying to fix them (HSE,). In most of the cases, the work environment providesbehaviors that cause a poor posture and cumulative trauma to the workers (Oakley & Smith, 2000).According to (HSE, 2015) such issues should be included in the ergonomic risk assessments which is a five stage process that involves:
• Looking for the hazards
• Deciding who might be harmed and how
• Evaluating the risks and deciding whether the existing precautions are adequate or whether more should be done
• Recording the findings and telling the employees about them
• Reviewing the assessment and revising it if necessary
The role of ergonomics is to evaluate the individual, the job and the work environment and make changes in the job or the work environment to meet the individual needs (Fernandez, 1995).
The main purpose of the ergonomic assessment is to identify the risk factors that affect the individuals’wellbeing; productivity and safety in the work environment and plan strategies that help in minimize these risk factors (OSHA, 2000).According to OSHA (2000) ergonomics relay on many scientific disciplines such as physiology, psychology, anthropometry, industrial hygiene, biomechanics, and kinesiology. As noted in (HSE, 2013) the ergonomic assessmentsassess the fit between the individuals and their job which consider a range of factors such as:
? Identify the worker task (activities, workload, work pacing, shiftwork and fatigue).
? The design of the equipment used in terms of size, shape, controls, displays, and how suitable it is for the task.
? The information used (how it is presented, accessed, and changed).
? The physical environment (temperature, humidity, lighting, noise, vibration).
?The individual’s physical and psychological characteristics:
? Body size and shape.
? Fitness and strength.
? The senses, especially vision, hearing and touch.
? Mental abilities.
? Experience. ?
The organisation and social environment:
? Teamwork and team structure.
? Supervision and leadership.
? Supportive management.
What is assessed?
In general, ergonomic assessments focused on the work environment and the workstations design (Oakley & Smith, 2000). There are many risk assessment methods and they are used depending on the assessed work nature, workstations and the equipment’s used. Some of these assessments are designed to evaluate the user and some are designed to evaluate the workstations and the work environment.
Starting with the WRMSD, there are a number of risk assessment methods that should be selected appropriatelydepending on each part of the human body and/or the MSD hazards.
1. Checklist methods (multiple hazards considered)
• MSD hazard risk assessment checklist
2. Manual materials handling (lifting, lowering, pushing, pulling, carrying)
• Snook tables: These are tables of maximum acceptable weights and forces for a variety of manual handling operations, including lifting, lowering, pushing and pulling. They are based on extensive experiments using industrial workers adjusting the loads being handled until they had selected loads that they considered they could handle for the duration of a work shift without excessive strain or fatigue (Snook and Ciriello, 1991; Snook, 1978).
• Manual Handling Assessment Chart (MAC) (UK): These are the flowcharts being benchmarked in this study. Attention is focused primarily on the Lifting flowchart, but many of the factors in the Team Handling and Carrying flowchart are common to it.
3. Upper limb
• Rapid Upper Limb Assessment (RULA): is a tool used to assess the risk of musculoskeletal loading, especially on the upper limbs and neck, associated with the postures, forces and movements inherent in a task (McAtamney&Corlett, 1993).
• Strain index
4. Combined methods (not checklist)
• Quick Exposure Check (QEC): Its purpose is to be a user friendly practical tool for the assessment of physical exposure to risks for work-related musculoskeletal disorders (Li and Buckle, 1999).(HSE, 2002)
• Rapid Entire Body Assessment (REBA): This was developed as a postural analysis tool to be sensitive to the type of unpredictable working postures found in health care and other service industries (Hignett and McAtamney, 2000). Its approach and scoring system are clearly based on RULA (Rapid Upper Limb Assessment) (McAtamney and Corlett, 1993).
• Man TRA
• OWAS :This is a method of coding the posture of a worker that allows the harmfulness of the posture to be categorised into four Action Categories of increasing urgency. It is based upon expert judgements of the harmfulness of particular postures. A time-based sampling approach can be used with it so that the categorisation can take account of the length of time spent in any particular posture (Karhuet al., 1977, 1981, Kivi and Mattila, 1991, Vedder, 1998).
It was developed by the National Institute of Occupational Safety and Health in the USA. It is a multiplicative equation that uses parameters of the job to predict a Recommended Weight Limit which is believed to be safe for most workers to handle (Waters et al., 1994, NIOSH 1981).
In a pilot study done in Kolkata,West Bengal by Chandra, Gosh, Berman &Chakravati (2009) about ergonomics issues in academic libraries, the researchers emphasis on the need to design the academic libraries to meet the 21 century needs such as teaching, learning and research. In this study Chandra et.al, (2009) mentioned three goals in human centered ergonomic design.
1. Improve human abilities
2. Overcome human limitations
3. Foster user acceptance (paraphrase)
Considering the key factors in the ergonomic assessment of this syudy to achieve the previous goals, which are:
1. Workstation design: work surfaces, chairs and accessories
2. Environment: lighting, noise level, air quality space planning, thermal factors, etc.
In an article written by (Rooney, 1994) about ergonomics in academic libraries, the author shed the light on many aspects such as the human nervous system. Rooney (1994) stated that the nervous system is responsible about communication inside the body and about communication of the body with its surrounding. Rooney (1994) noted that people experience the life through the sense organs; this led him to examine the eyes, ears and skin in this article, as they are the most relevant aspects related to ergonomics. Rooney (1994) indicated in his study that the skin considered as the important aspects of the sense organs in relation to ergonomics. The importance of the skin comes from the nerve endings and the sweat glands within the skin dermis, which is responsible about regulating the body temperature by sweating, and is sensitive to pain, temperature and touch.
Rooney (1994) focused also on the library furniture design in relation to the human body. Starting with the chairs, the author stated that the majority of chairs founded in the academic libraries are uncomfortable and nonadjustable. Rooney (1994) noted that consideration should be given to the seat characteristics in the academic libraries especially to the width and depth. Stating that the ideal seat width should be 400mm as minimum (Pheasant, 1987, p. 144) and the ideal seat depth should be 380mm to 470mm (Pheasant, 1987, p. 144). Moreover, Rooney (1994) stress the importance of the adjustable height seats that should be from a minimum height of 240 mm to a maximum of 500mm and the adjustable backrest that should have a height of 170 mm to 250 mm with the height of the rest being 100 mm (Pheasant, 1987, p. 144). Rooney (1994) study shed the light on the desks that many students find it uncomfortable and low, footrest that can be comfortable for short users but they are often overlooked in the academic libraries. In addition to shelving that should be in a convenient height for the users with a minimum distance between stacks of 419 mm.
Rooney (1994) study focused on some aspects that considered in this study such as lighting, he stated that lighting is one of the most aspects in library design. According to (LA, 1990) the recommended illumination in general library study areas should be between 400-600 lux. The author also stress the need of the natural lighting, (Rooney, 1994) stated that carrels and tables should be placed close to the window because of the positive psychological effects of light on the users while the negative effects such as glare brightness and shadows can be overcome by using blinds to defuse the light. Another similar aspect in Rooney (1994) study was the noise. According to Smith (1990) the library users performance and concentration could be negatively affected by high level of noise. The effect of noise could be physiological such as fatigue, headache and ringing in the ear, and the psychological effects could be loss of concentration. The students interviewed in Rooney (1994) study preferred a low-level background noise to deadly silence.
Heating, humidity and ventilation were also important ergonomic aspects in (Rooney, 1994) study. It was noted that the ideal temperature of a library is between 20-22 degrees centigrade, while the correct humidity level should be between 50-55 per cent and ventilation in the libraries is important to remove impurities in the air and create a fresh and healthier environment. Rooney (1994) discussed many aspects such as flooring, visual display units, space in libraries, colour in libraries etc. The study concluded that most of the students interviewed for the article were not aware of the meaning of the word ergonomics. Moreover, the study stress on the role of the library managers in giving more attention to the library users and staff working areas and recommended to follow (Bawa, 1992) 45 steps towards ergonomic perfection.
Computer workstation assessment:
After the ergonomic evaluation is performed and major problem areas are addressed, each workstation should be assessed to: 1) reduce static muscle load; 2) reduce awkward postures; 3) improve task design (physical and mental capacities); 4) improve workplace/equipment design; and 5) improve work organization (take rest breaks, reduce shifts). According to Fernandez (1995) the aim of the ergonomic is o fit the job to the individual and not the opposite.
HSE(2013) http://www.hse.gov.uk/pubns/indg90.pdf retrieved in 20July(2015) 06:39 pm
Oakley, J. S., & Smith, S. M. (2000). Ergonomic: Assessment & design. Professional Safety, 45(2), 35. ? Link(HSE, 2015) http://www.hse.gov.uk/msd/risk.htm Retrieved 19July, 2015
(HSE, 2002) RETRIVED FROM: http://www.hse.gov.uk/research/hsl_pdf/2002/hsl02-31.pdf IN 19JULY 2015 01:74 AM