Introduction to Ergonomics presented to GWU PT program 12/8/10

1. Introduction to Ergonomics Naomi Abrams, MOT, OTR/L GWU December 2010 © Worksite Health & Safety Consultants, 2010

2. Course Objectives Participants will leave this session with An understanding of the contextual influences and psychosocial demands of the work environment An understanding of the connection of work activities with repetitive strain disorders Methods to identify and measure the hazards commonly faced by workers Methods to actively involve workers in addressing worksite hazards © Worksite Health & Safety Consultants, 2010

3. History of Ergonomics Ergon (work) + Nomos (principle of law) 1700 – Bernardino Ramazinni (1633-1714) wrote about work-related injuries that he saw in his medical practice. 1857 – WojciechJastrzebowski first used the word to describe the “Science of Work”. However, good tool fit has been explored since people started using tools! © Worksite Health & Safety Consultants, 2010

4. What is Ergonomics OSHA 1999: Ergonomics is the science of fitting jobs to people. Ergonomics encompasses the body of knowledge about physical abilities and limitations as well as other human characteristics that are relevant to job design. Ergonomic design is the application of this body of knowledge to the design of the workplace (i.e., work tasks, equipment, environment) for safe and efficient use by workers. Good ergonomic design makes the most efficient use of worker capabilities while ensuring the job demands do not exceed those capabilities. (Ergoweb, 2003) © Worksite Health & Safety Consultants, 2010

5. OSHA Osha.gov NIOSH Cdc.gov/niosh Human Factors and Ergonomic Society hfes.org Board Certification of Professional Ergonomists bcpe.org American Industrial Hygiene Association aiha.org American Society of Safety Engineers asse.org International Ergonomics Association iea.cc Chesapeake Region Safety Council (local) chesapeakesc.org Business and Institutional Furniture Manufacturer’s Association bifma.org © Worksite Health & Safety Consultants, 2010

6. Components of Work Cognitive requirements Psycho-social requirements Context/environment influences Physical requirements © Worksite Health & Safety Consultants, 2010

7. Ergonomic risk factors Awkward postures Static postures Forceful exertions Repetition Vibration Environment Temperature Lighting Fumes/Smells Recovery time Precision/control required © Worksite Health & Safety Consultants, 2010

8. Terminology Administrative control: procedures or methods that are put in place to change how a task is done (i.e., employee rotation, adjusting work pace, changing schedules) Engineering control: changing the physical environment of the job to decrease exposures (i.e. changing tools, changing rigging, using adjustable chair) Individual factors: a person’s physical, cognitive and psychological characteristics © Worksite Health & Safety Consultants, 2010

9. Common Injuries Low back strain or herniated disc Rotator cuff syndrome Carpal tunnel syndrome Lateral/medial epicondylitis Think -- cause and effect. Think -- when do you do this? © Worksite Health & Safety Consultants, 2010

10. The ergonomic evaluation process Observation begins before you even enter the room. Look around for how the hallways are arranged, the looks on peoples’ faces, the temperature, the ambient sounds. Interview: What is the problem in their words. How have they tried to fix it. How would they fix it. Psychosocial factors Pain scale rating or pre-test: measure what you hope to change (i.e., pain, efficiency, stress level). Measurement and recording of the job requirements. © Worksite Health & Safety Consultants, 2010

11. First What do they do? Why do they do it that way? © Worksite Health & Safety Consultants, 2010

12. The scientific method of analyzing risk… Ergonomic risk factors: Awkward postures Static postures Forceful exertions Repetition Vibration Environment Temperature Lighting Fumes/Smells Recovery time Precision/control required NIOSH © Worksite Health & Safety Consultants, 2010

13. NIOSH lifting equation Yields a maximum safe lifting weight based on the position of the object at the origin and the destination, the distances of the lift, and the lifting frequency Can be used to analyze a single lift or multiple lifts Cannot be used when there is a tool involved (shovel, straps, lever) Does not take into account what happens during a lift (going over a barrier or through an access panel) © Worksite Health & Safety Consultants, 2010

14. Lift © Worksite Health & Safety Consultants, 2010

15. V = Mid-Point Between Inner Ankle Bones Point of Projection H © Worksite Health & Safety Consultants, 2010 From: Ergoweb Jet Toolbox

16. Sagittal Plane Frontal Plane A Sagittal Line Point of Projection A = degrees © Worksite Health & Safety Consultants, 2010

17. Origin Destination © Worksite Health & Safety Consultants, 2010

18. NIOSH lift analysis: lifting from crib part 1 (bed to rail height) Data Form 1:Record Object Weight: Average 22 lb. Maximum 40 lb. 2: Record Origin Measurements: Horizontal:12 in. Vertical: 33 in. Asymmetry: 30 deg. 3: Record Destination Measurements: Horizontal: 8 in. Vertical: 54 in. Asymmetry: 0 deg. 4: Record Lifting Frequency (Repetition) Frequency 0.02 lifts/minute 5: Select Lifting Task Duration Select: Short 6: Select Coupling Classification Select: Poor © Worksite Health & Safety Consultants, 2010

19. Multiplier Tables Origin and Destination values are then referenced on a NIOSH table to get the “multiplier.” Example: Height multiplier: 10/Height at origin = 10/12=0.83; Vertical multiplier: 1 - (.0075 |V-30|) So, our mom: Origin: weight max=30.6 lb Destination: weight max=34.1 lb © Worksite Health & Safety Consultants, 2010

20. Calculations and more… www. Ergoweb.comJET Toolbox Max tested wt/max calculated wt = lifting index Origin lifting index: 40 lb./ 30.6 lb. =1.3 Destination lifting index: 40 lb. /34.1 lb. =1.2 Lifting index: <1 ok; 1-3 concern; >3 needs change © Worksite Health & Safety Consultants, 2010

21. Break © Worksite Health & Safety Consultants, 2010

22. The office environment ANSI/HFES 100-2007: Human Factors Engineering of Computer Workstations Designed mostly for furniture manufacturers, not as a guide for ergonomic evaluations Only applies to a standard computer used on a desk. Does not take into account laptops or alternative computer set-ups. Does not address the health of the operator or work practices. © Worksite Health & Safety Consultants, 2010

23. Rules? NO 90-90-90 © Worksite Health & Safety Consultants, 2010

24. 4 basic computing positions The best position is one you don’t stay in for a long time. © Worksite Health & Safety Consultants, 2010

25. The computer workstation assessment The “VDT” Checklists There is no one standard checklist. You can find or make any number of versions. Only serves as a guide to be sure you look at all parts of the workstation (equipment, environment, task, and person) © Worksite Health & Safety Consultants, 2010

26. First: what do they do and why? Assess what type of work the person does. Constantly on e-mail = more mouse work Editing from books = needs more space Doing two things at once = may need hands-free devices Why do they do what they do? Habit versus job requirement Time constrictions that are self-imposed versus demanded Cognitive demands exceed ability © Worksite Health & Safety Consultants, 2010

27. Second: where do they work? Visual scan of the environment Q&A about the environment (temperature, noise, etc.) Psychosocial demands: not really a Q&A, more therapeutic use of self © Worksite Health & Safety Consultants, 2010

28. Third: why were you contacted? Where they hurt can give you great insight into what is wrong. “Mostly, my neck hurts.” © Worksite Health & Safety Consultants, 2010

29. Only now can you get into equipment. Seating Keyboard Mouse Monitor Phone Paperwork Other © Worksite Health & Safety Consultants, 2010

31. Raise or lower the chair so that the knees are approximately even with the hip joint.

32. The seat should be 3-4 finger widths from the popliteal fold.

33. Adjust the seat tilt so that the seat pan (the part you sit on) is level with the floor or tilted back slightly.© Worksite Health & Safety Consultants, 2010

35. Should be leaning backwards slightly (try for a 110-135° hip/trunk angle).

36. Feel the contour of the back and compare it to the contour of the chair especially at the small of the back. The chair should fully support the back’s natural curves*.

37. Back rest should support the body without blocking the movement of the shoulder blades.© Worksite Health & Safety Consultants, 2010

38. “ergonomic” chairs © Worksite Health & Safety Consultants, 2010

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40. Supports may be needed Use caution! Too much padding may result in seat depth problems. © Worksite Health & Safety Consultants, 2010

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42. Keyboard and mouse Rule: elbows down by the sides. Rule: wrists straight. Everything else is negotiable. © Worksite Health & Safety Consultants, 2010

43. “ergonomic” keyboards and mice © Worksite Health & Safety Consultants, 2010

44. Monitor(s) should be Front and center Approximately 22-24 inches from the face depending whether the user has glasses Set so that the top portion of the screen that is used most often is at eye level. Positioned so that the zygomatic arch/maxilla are level. © Worksite Health & Safety Consultants, 2010

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48. Phone use Use a hands-free device if required to type or write while on the phone. The phone should be on their non-dominant side. The reach distance depends on use frequency. © Worksite Health & Safety Consultants, 2010

49. The reach envelope Sanders and McCormick, 1993, p 432 © Worksite Health & Safety Consultants, 2010

50. Paperwork and lighting Assess focal length For reading, it is typically 16-18 inches. Assess glare versus illumination © Worksite Health & Safety Consultants, 2010

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53. Simple changes yield better results than complex changes. “This is your personal space. Keep everything in it” (horizontal distance) Squaring off to item (asymmetry) Taking one step forward towards item (horizontal distance) Ask for help and accept it when offered (frequency) Use everyday items to change surface heights Use a step stool (vertical distance) Put hard to handle items in a container or on a push cart (coupling and horizontal distance) Use shelves instead of baskets/buckets on floor for items (vertical distance) © Worksite Health & Safety Consultants, 2010

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55. Simple changes – problem solving with the client Pacing, Prioritizing, Positioning Using a dining room chair instead of the couch Use a pillow under books when reading in bed or on couch Use a cookbook holder when reading at table Keep frequently needed tools in multiple places (such as scissors where the mail is opened) Rearrange items and shelves – where are the heavy items? © Worksite Health & Safety Consultants, 2010

57. The ergonomic process Observation Measure/evaluate: homemade checklist or standardized tools like the NIOSH Justify need for correction Goal setting Change: administrative, engineering, or individual/person Re-measure/re-evaluate Return on investment (ROI) © Worksite Health & Safety Consultants, 2010

58. Thank you Naomi Abrams, MOT, OTR/L, CEAS 240-912-9559 Naomi@WorkInjuryFree.com © Worksite Health & Safety Consultants, 2010

59. References and Suggested Reading Anders, M. J., & Morse, T. (2005). The ergonomics of caring for children: An exploratory study. American Journal of Occupational Therapy, 59, 285-295. Care for cargivers (2003). CareGuide@Home [on-line]. Available: http://www.eldercare.com/modules.php?op=modload&name=CG_Resources&file=article&sid=861. Ergoweb (2003). Applied Workplace Ergonomics Manual. Ergoweb, Inc. Ergoweb (2003). Fundamentals of Office Ergonomics. Ergoweb, Inc. Franklin, B. A., Hogan, P., Bonzheim, K., Bakalyar, D., Terrien, E., Gordon, S., & Timmis, G. C. (1995). Cardiac demands of heavy snow shoveling. JAMA. 273 (11), 880-882. Gauthier, A. H., Smeeding, T. M., & Furstnburg, F. F. (2004). Are parents investing more or less time in children. (Policy Brief) Canadian Research Institute for Social Policy. Available at www.unb.ca/crisp/pbrief.html. Griffin, S. D., & Price, V. J. (2000). Living with lifting: Mothers’ perceptions of lifting and back strain in childcare. Occupational Therapy International, 7 (1), 1-20. Gunn, S. M., van derPloeg, G. E., Withers, R. T., Gore, C. J., Owen, N., Bauman, A. E., & Cormack, J. (2004). Measurement and prediction of energy expenditure in males during household and garden tasks. European Journal of Applied Physiology. 91(1), 61-70. Herr, N. (2007). Television & health. Retrieved from http://www.csun.edu/science/health/docs/tv&health.html. Hinojosa, J., Kramer, P., & Pratt, P. N. (1996). Foundations of practice: Developmental principles, theories, and frames of reference. In J. Case-Smith, A. S. Allen, & P. N. Pratt (Eds.), Occupational therapy for children (pp. 25-45). St. Louis, MO: Mosby. © Worksite Health & Safety Consultants, 2010

60. Human Factors and Ergonomics Society (2007). ANSI/HFES 100-2007 Human Factors Engineering of Computer Workstations. HFES. http://hfes.org. Iwakiri, K., Sotoyama, M., Mori, I., & Saito, S. (2007). Does leaning posture on the kitchen counter alleviate workload on the low back and legs during dishwashing? Industrial Health. 45, 535-545. Jarus, T., & Ratzon, N. Z. (2005). The implementation or motor learning principles in designing prevention programs at work. Work, 24, 171-182. Juan, W., & Britten, P. (2008). Routine active and sedentary behavior patterns in U.S. adults. (USDA Nutrition Insight 40). Alexandria, VA: USDA. Luria, G., Zohar, D., & Erev, I. (2008). The effects of workers’ visibility on effectiveness of intervention programs: Supervisory-based safety interventions. Journal of Safety Research, 39, 273-280. Macera, C. A., Jones, D. A., Yore, M. M., Ham, S. A., Kohl, H. W., Kimsey, C. D., & Buchner, D. (2003). Prevalence of physical activity, including lifestyle activities among adults – United States, 2000-2001. MMWR, 52(32), 764-769. McDaniel, M. A., Howard, D. C., & Butler, K. M. (2008). Implementation intentions facilitate prospective memory under high attention demands. Memory & Cognition, 36 (4), 716-724. National Heart, Lung, and Blood Institute. (2005). Your guide to healthy sleep. (NIH Pub No. 06-5271). Washington, DC: U.S. Department of Health and Human Services. OSHA. (2005). Guidelines for nursing homes: Ergonomics for the prevention of musculoskeletal disorders. Washington, DC: U.S. Department of Labor. © Worksite Health & Safety Consultants, 2010

61. Pirie, A., & Herman, H. (1995). How to raise children without breaking your back. W. Somerville, MA: IBIS Publications. Sames, K. M. (2005). Documenting occupational therapy practice. Upper Saddle River, NJ: Pearson/Prentice Hall. Sanders, M. S., & McCormick, E. J. (1982). Human factors in engineering and design (7th ed.). New York: McGraw-Hill. Williams, S., & Cooper, L. (1999). Dangerous waters: Strategies for improving wellbeing at work. New York: Wiley. Yousey, J. (2002). A field guide for families: How to assist your older loved ones when you don’t live next door. Niantic, CT: Life Design Publishing. Zoltan, B. (1996). Vision, perception, and cognition (3rd ed.). Thorofare, NJ: SLACK Inc. © Worksite Health & Safety Consultants, 2010

62. Low back strain and “herniated discs” Common causes at work: Improper lifting/pushing/pulling technique Lifting too much Sitting incorrectly Sitting too long (even in the correct position) Reaching too far Lifting “cold” (without stretching) © Worksite Health & Safety Consultants, 2010

63. Rotator Cuff Syndrome Common causes at work: Reaching behind to lift Repeated reaching overhead Poor postural and shoulder muscle strength © Worksite Health & Safety Consultants, 2010

64. Carpal Tunnel Syndrome Common causes at work: Frequent gripping Constant wrist bending Direct pressure on the wrist from straps or tools Vibration © Worksite Health & Safety Consultants, 2010

65. Elbow pain (lateral and medial) Common causes at work: Frequent gripping with reaching or turning Frequent hook grasp Constant mouse use with an extended arm © Worksite Health & Safety Consultants, 2010

66. Case Studies Group 1: 25 lb. box From under the table Put onto the table Group 2: 50 lb. bag From next chair over (2 chair widths away) Put on table Group 3 40 lb. box with two handles From table on right of room Put on table on left of room © Worksite Health & Safety Consultants, 2010

67. Patient driven goals AOTA 1998 Standard V: “client centered goals that are clear, measurable, behavioral, functional, contextually relevant and appropriate to the client’s needs, desires, and expected outcomes” (Sames, 2005) © Worksite Health & Safety Consultants, 2010