Why Ergonomics?• A field of study that has contributed to the understanding of work- related stresses and solutions, anatomy and physiology, anthropometrics, biomechanics, psychology, and industrial design and engineering.• DEFINITION:• “ The application of a body of knowledge (life sciences, physical science, engineering etc.) dealing with the interactions between man and the total working environment, such as atmosphere, heat, light and sound, as well as tools and equipment of the workplace.” -Industrial Engineering Terminology (revised edition, 1991)
Main Aim of Ergonomics• “Aims to make sure that tasks, equipment, information and the environment suit each worker.”• Increases productivity due to • Less fatigue, • Safer working environment (lesser accidents), • Lesser absenteeism and • Reduced labor turnover.
Factors affecting Ergonomics • Ageing• Climate • Material Handling – Temperature, – Humidity, and • Stress or Strain, and – Airflow-Ventilation. • Load• Noise,• Illumination,• Vibration and Radiation,• Work Time/ Shift,• Work Overload,
Area Of Ergonomic Intervention• Human-machine interface,• Environment,• Hardware, and• Work Posture
Human-machine Interface• Display • As clear and as easy to read as possible. • Must meet the needs of the human operating the machine/ equipment.• Text clarity • KISS (Keep It Short and Simple) principle. • The readability should be as per Gunning Fog Index.• Control- factors to be accounted for • Force • Speed • Grouping • Accuracy • Illumination • Population stereotypes.
Environment• Workplace Layout • The tendency of operators to work in the hunched posture also suggests a potential conflict between workstation geometry and operator dimensions.• Automation • can reduce the skill of requirements of a complex positioning and guiding task . • also eliminate many high-risk hand and wrist postures and the frequency of hand movements, thereby reducing the exposure to common repetitive trauma disorders.• Manufacturing system • Modular manufacturing reduces repetitive strain injuries. • A period of adjustment decreases levels of musculoskeletal discomfort (due to increase in the variety of movements and improve postures at the standing workstation). • Increases morale and workgroup cohesiveness, along with substantially reduced absenteeism.
Hardware• Seating • The vast majority of operations are performed in a seated position. • Right combination of stool and table height is essential for correct posture- customizing table and stool height combination shows improvement of performance and reduction of SAM value by 4-12%.• Attachments, Work-aids & Tools • Avoids the awkward posture of wrists, hands and fingers throughout the operation. • For example- the automated felled seamer for the double overlapped seam allows the operator to use nearly neutral wrist and hand postures throughout the operation.
Work Posture• Improvement through training.• Much of the reported discomfort in the back and neck can be attributed to the working postures of the seated operators/workers.• In response to job and workstation characteristics, operators typically adopt a hunched working posture.• The tendency of the workers to work in this hunched position can be attributed to at least three factors – The visual demand of the work, – The geometry of the workstation, and – Inadequate seating (which can be corrected by using right equipment).
Discussed Article• Office Workers Are At High Risk Of Postural Problems Costing Businesses Millions - David McCall, Steelcase, Consultant PUBLISHING DATE- 23/11/2010
Introduction of Steelcase• Steelcase are global leaders in workspace design and office interiors, specialising in the world of work, workplace and workers focusing on ergonomics.• Over the last 35 years Steelcase has produced some of the most thorough research in terms of ergonomics and spinal movement leveraging this knowledge to the development of its high performance seating and workstation products.
About the Article• Central Focus of The Article • “Inadequate seating posture and working aids for office workers.”• Work related "musculo-skeletal disorders" such as back injuries are the most prevalent, most expensive and the most preventable workplace injuries in the country.• Also finger injuries due to continuous work in a fixed posture on the computers• Back injuries causes: • Decrease in employee health resulting increase in employee absenteeism. • Decrease in productivity. • Decreased ability to attract and retain the best talent.
Repetitive Strain Injuries And Disorders1.Back• Herniated spinal disc. • The spinal disc is a soft cushion that sits between each vertebrae of the spine. This spinal disc becomes more rigid with age. In a young individual, the disc is soft and elastic, but like so many other structures in the body, the disc gradually looses its elasticity and is more vulnerable to injury. As the spinal disc becomes less elastic, it can rupture. When the disc ruptures, a portion of the spinal disc pushes outside its normal boundary- this is called a herniated disc. • Symptoms – Electric shock pain, – Tingling & Numbness, – Muscle Weakness & – Bowel or Bladder Problems
Repetitive Strain Injuries And Disorders1.Back• Low Back Pain • This refers to pain in the lumbosacral area of the spine encompassing the distance from the 1st lumbar vertebra to the 1st sacral vertebra. This is the area of the spine where the lordotic curve forms. • The most frequent site of the low back pain is in the 4th and 5th lumbar segment.
Repetitive Strain Injuries And Disorders2.Fingers• Trigger finger • Tenosynovitis causes the finger to “stick” in a flexed position, this is called “stenosing” tenosynovitis which is commonly called “Trigger Finger”.
About the Study• 200 employees from a state agency that collects sales tax in the USA, volunteered for one year to participate in the study.• To qualify each participant had to spend at least six hours a day sitting in their chair.• The volunteers were divided into three groups: • Control group. • A group that received ergonomic training. • A group that received ergonomic training and the Steelcase Leap Chair.
Results of the Study• Remedies Suggested by the Study – Working aids like Steelcase’s Leap chair, seating posture aid (used for the study) in a conjunction with a user training show significant improvements in health and productivity. – lower pain and discomfort in work environment.• Showed an increase in the productivity. – After one year, the Leap chair with training achieved a 17.8% increase in productivity. – This number reflects the increase in taxes collected per hour worked.
Findings of the Study• “ Ergonomics is more important than people realise, we spend 84% of our working time in the seated position and in excess of 80,000 working hours sitting down. This can have a negative effect on the body and the overall health.” – Companies may benefit by improving the seating provided to their office workers along with training on how to use them. – Training is key as two thirds of office workers do not adjust their chair.
Summary of the Study• Technology and the modern office are the most important and largest factors affecting the development of ergonomics. The introduction of computers forced the workers to adopt a static slumped portion, which increased musculo-skeletal disorders, fatigue and stress. Technology has moved forward and introduced I -Phones, I-Pads and laptops, mean people can work anywhere. Back health care needs to be fully understood within businesses, organisations need to help their employees by providing the right tools and training to provide the best working environment wherever they are.
• TIME STUDY • Hem Seam • Lapped Felt Seam
Hem Seam (summation of time)Element 1 2 3 4 5 6 7 8 9 10Lifting the 11.30 10.79 11.00 11.12 10.98 11.20 10.85 11.53 11.23 11.21fabric from theside table withleft handplacing it onsewing tableFolding the 23.06 22.89 23.23 23.43 23.43 22.00 23.06 23.12 23.26 23.12fabric withboth hands at½ “ twiceStart edge 29.86 28.69 29.00 28.56 28.50 28.30 28.12 28.57 28.57 28.16stitchTrimming the 37.59 37.70 37.80 39.50 37.85 38.10 37.98 37.78 38.09 38.02thread anddisposing thesample on theside table
Hem Seam (individual time for eachelement)Element 1 2 3 4 5 6 7 8 9 10 avgLifting the 11.30 10.79 11.12 10.98 11.20 10.85 10.85 11.53 11.20 11.21 11.21fabric fromthe side tablewith left handplacing it onsewing tableFolding the 11.76 12.10 12.23 12.31 12.52 10.80 12.21 11.59 12.03 11.91 12.07fabric withboth handsat ½ “ twiceStart edge 6.80 5.80 5.77 5.13 5.00 6.30 5.06 5.50 5.31 5.04 5.32stitchTrimming the 7.73 9.01 8.80 10.94 9.35 9.80 9.86 9.16 9.52 9.87 9.40thread anddisposing thesample onthe side table
Calculations:• Standard rating – 95%• Basic time=38X(95/100) =36.1 sec• Allowance – 5%• Standard time = 36.1+1.80• =37.90 sec
Lapped Felt Seam (summation of time)Element 1 2 3 4 5 6 7 8 9 10Lifting the 11.84 12.00 11.73 11.40 11.68 11.42 11.65 11.85 11.59 11.20fabric from theside table withleft handplacing it onsewing tablePlacing the 25.00 25.23 24.89 25.26 24.95 25.18 25.72 25.60 25.43 24.09fabric onanother at ¼ “and edgestitchFolding & 35.32 35.73 35.12 36.00 35.23 35.19 35.81 35.32 36.12 35.32turning the 0sample thenedge stitchingTrimming the 42.13 41.88 42.18 43.10 42.09 43.00 42.13 42.75 43.00 42.63thread anddisposing thesample on theside table
Lapped Felt Seam (individual time foreach element of process)Element 1 2 3 4 5 6 7 8 9 10 avg .Lifting the 11.84 12.00 11.73 11.40 11.68 11.42 11.65 11.85 11.59 11.20 11.70fabric fromthe side tablewith left handplacing it onsewing tablePlacing the 13.16 13.23 13.16 13.86 13.27 13.76 14.07 13.75 13.84 13.89 13.55fabric onanother at ¼“ and edgestitchFolding & 10.32 10.50 10.23 10.74 10.28 10.01 10.09 9.72 10.69 10.23 10.34turning thesample thenedgestitchingTrimming the 6.76 6.15 7.06 7.10 6.86 7.81 6.32 7.43 6.88 7.31 7.06thread anddisposing thesample onthe side table
Calculations:• Standard rating- 95%• Basic time= 42.65X(95/100) = 40.52 sec• Allowance- 5%• Standard time = 40.52+2.02 = 42.54 sec