Ergonomics- Standing and Sitting Work .pptx

This presentation is about the ergonomic design of standing and sitting jobs. Its impacts and what we should and should do. suitable for students and lecturers.

1. STANDING AND SITTING AT WORK Students : Aitaj Jafarova Speciality : Ecology engineering \ 3 Lecturer: Ilqar Xurshudov

2. Physiology of seated work 01. Physiology of standing work 02. Ergonomics for seated work 03. Ergonomics for standing work 04. TABLE OF CONTENTS

3. INTRODUCTION 01.

4. Intro Ergonomics plays a crucial role in promoting comfort, productivity, and overall well-being in the workplace. When it comes to standing and sitting work, it is important to maintain a neutral body position to minimize strain and reduce the risk of musculoskeletal disorders . Here are some key considerations for both standing and sitting work:

5. “ Humans are designed to walk on two legs, but they are not designed to stand still”

6. Posture Posture refers to the body's average orientation over time, ensuring balance and alignment. In a neutral posture, the skeleton is in balance, with joints close to their mid-point of motion. Forward flexed postures, especially when sitting, can double disc pressure, increasing lumbar spine stiffness. This can cause low back pain and increase injury risk, especially for manual tasks like offloading deliveries .

7. Static postures Standing or sitting stationary is medically and mechanically inacceptable because brief periods of walking and large-scale body movements are necessary for blood return from lower limbs. When standing for long durations, people frequently use standing assistance like a sentry's spear or a herdsman's staff. Low back pain is linked to prolonged everyday standing. Static work should be avoided and jobs should be changed to provide relief from static postures in order to prevent health concerns.

8. Physiology of sitting work

9. Spinal problems in sitting

10. Prolonged sitting for over 95% of the day is associated with back pain. Many people with bad backs gravitate towards sedentary work, and poor design of workstations causing flexed sitting postures may exacerbate existing problems Professional drivers, pilots, and operators of machines, such as forklift trucks, often experience back pain due to static seated work SPINAL PROBLEMS IN SITTING

11. 15% Sitting for 8-11 hours per day and more hours per day increases the risk of mortality by 15% and 40%, respectively 112/147/90% Sedentarism is associated with a 112% increased risk of diabetes, 147% increase in cardiovascular events, 90% increase in cardiovascular mortality, and 49% increase in all-cause mortality 49% Therefore, postural variety and movement should be designed into jobs to reduce the risk of mortality

12. Physiology of standing work

13. Prolonged standing Prolonged standing causes physiological changes, including peripheral pooling of blood, decreased stroke volume, increased heart rate, diastolic and mean arterial pressure, peripheral resistance, and thoracic impedance. Constrained standing is particularly problematic for older workers or those with peripheral vascular disease, as the "venous muscle pump" ceases to function. Fidgeting is a preconscious defense against postural stresses of constrained standing or sitting, aiming to redistribute and relieve loading on bones and soft tissues.

14. Musculosceletal problems in standing Standing workers often experience low back pain. Standing can cause low back pain due to muscular fatigue and excessive trunk extension, lateral flexion, or twisting Excessive lumbar lordosis can stress the soft tissues around the joint, causing low back pain. To avoid this , it is recommended to avoid standing with a pronounced lumbar lordosis. Workspace or task factors that require workers to arch the back greater than usual should be designed out. Poor workstation design can lead to stressful standing postures, causing spinal problems. Constrained standing and older age are associated with increased risk of pain, highlighting the need for standing workers to have freedom to sit.

15. Low back pain, muscular fatigue and lumbar lordosis

16. 9.4% of standing workers reported ankle or foot pain and 6.4% lower leg or calf pain in the 12 month period preceding their investigation.

17. Workspace for standing work

18. Standing Aids Footrest In a standing workplace, workers benefit from a footrest that supports their foot, allowing them to stand with one foot forward and elevated, reducing lumbo-pelvic constraint and promoting plantar flexion. Compression stockings Standing workers are at higher risk of varicose veins, causing painful swelling. Risk factors include obesity, smoking, high blood pressure, and lack of exercise. Compression stockings may reduce leg swelling, but not significantly. Toespace Toespace is a device designed to prevent postural adaptations, preventing users from standing further away from work surfaces due to pelvic tilting and lumbar flexion, using pelvis as part of legs.

19. Application of Ergonomics User characteristcs Task demands Workspace layout Ergonomic workstation design promotes good posture, with a framework emphasizing the interaction of three variables. Studies show that task demands, workspace layout, and user characteristics can affect trunk loading and kinematics.

20. A person’s working posture is a result of the requirements of the task, the design of the workspace, and personal characteristics such as body size and shape and eyesight. Consideration of all three components is needed in posture analysis and workspace design. THE POSTURAL TRIANGLE

21. Factors that Influence Working Posture User Characteristics Age Body weight Fitness Joint mobility Existing musculoskeletal problem Previous injury/surgery Eyesight Handedness Obesity Task Requirements Visual requirements Manual requirements Positional Forces Cycle times Rest periods Paced/ unpaced work Workspace design Seat dimensions Work surface dimensions Seat design Workspace dimensions Headroom Legroom Footroom Privacy

22. 2 3 1 THREE STEPS OF EFFECTIVE WORK STATION Postural requirements Visual reqiurements Temporal requirements

23. The neck's posture is determined by visual requirements, with binocular overlap occurring 15° either side of the straight-ahead line of sight. This helps avoid static loading of neck muscles and soft tissues. Visual Requirements

24. Position task objects in convenient reach for posture and postural load, and vehicle design's driver's seat comfort depends on its positioning, design, and alignment with foot pedals and manual controls Postural Requirements

25. The workstation design is influenced by the temporal requirements of tasks. For multiuser computer workstations, a high bench and stool may be appropriate, while data entry jobs require repetitive tasks over the day. Temporal Requirements

26. Ergonomics of Seated work

27. The postural requirements for sedentary work should be met using modern office chairs with adjustable backrests, footrests, and lumbar supports , with task objects and visual targets placed within reach and optimal visual field.

28. Sedentary workers should position their main working area directly in front of their body to minimize twisting of the spine. The twisting mobility of the human back increases in sitting compared to standing. Jobs involving asymmetric handling of loads from a seated position, such as supermarket checkout personnel, are particularly hazardous Work Surface Design

29. Seated work Aids Adjustable Backrests Ergonomically designed workspaces should be flexible, accommodating multiple postures and a "designed-in" resting posture. Lumbar Support Lumbar supports optimize sitting postures by providing space for buttocks to protrude and tilting the pelvis forward. Foot Pump Devices A foot pump device designed to encourage plantar flexion can prevent leg swelling over an 8-hour day. Walking for 2 minutes every 15 minutes during an inactive day can also help prevent leg swelling.

30. CONCLUSIONS Ergonomics is crucial in designing ergonomic workstations, as it reduces postural stress and promotes physical activity.

31. THANKS !

32. RESOURCES SLIDE PHOTOS Google.com R.S.Bridger book Physiotherapy Icon Pack VECTOR All information is from the R.S.Bridger Ergonomics 4 th edition book