Ergonomic Management Manual

Transcription

1 Ergonomic Management Manual Section 1 Ergonomic Overview Section 2 Ergonomic Qualitative Analysis Section 3 Job Hazard Analysis Section 4 Manual Material Handling Job Hazard Analysis Section 5 Administrative Controls SAFETY TRAINING FROM THE PEAK OF EXCELLENCE

2 Introduction The goal of this Ergonomic Program is proactive prevention of musculoskeletal disorders through early identification, analysis, and control. The Ergonomic Management Series provides you with the tools and information necessary for reducing and preventing musculoskeletal disorders (MSDs). Why is ergonomic safety important? The Department of Labor, Bureau of Statistics, reports that musculoskeletal disorders account for 34% of lost workday illnesses and injuries. According to the most current statistical data, over 1.8 million workers suffer from musculoskeletal disorders each year. These injuries cost business $15 to 20 billion in workers compensation costs each year. The objective of ergonomics is to adapt the work environment to fit the worker - not make the worker fit the environment. This is accomplished through identifying ergonomic stressors, analyzing the data, and controlling the risk factors. The key elements for an effective ergonomic program are outlined and explained in this manual. The manual is divided into five sections: Section 1: Ergonomic Overview and Program Components Purpose of this Manual Why is Ergonomics Needed? Objective of Ergonomics How this Manual is Organized Section 2: Section 3: Section 4: Section 5: Ergonomic Qualitative Analysis Job Hazard Analysis Manual Material Handling Job Hazard Analysis Administrative Controls These guidelines provide a framework for a successful ergonomic program. Achieving that success requires cooperation and commitment from all levels of an organization. Acknowledgement Special thanks to Colin G. Drury, Ph.D., University at Buffalo, State University of New York, Department of Industrial Engineering, for sharing his expertise, knowledge, research, and offering valuable insights for the production of this manual. Summit Training Source, Inc. 1

3 Ergonomic Overview & Program Components What is Ergonomics? Goal of Ergonomics What are Musculoskeletal Disorders (MSDs)?..... Causes and Effects of MSDs Benefits of Ergonomics Ergonomic Program Components Safety Activity/Ergonomics Team Worksite Analysis Job Hazard Prevention and Control Medical Management Training and Education COPYRIGHTED BY SUMMIT TRAINING SOURCE, INC You may not duplicate these books without written permission from Summit Training Source, Inc. If you wish to purchase additional copies, please call our office at Summit Training Source, Inc. 2

4 Ergonomic Overview In simple terms, ergonomics is the science of fitting the job to the worker. It is not something new, but a science that has been studied and applied for decades. The word ergonomics was coined by a group of British scientists in 1950 from the Greek words ergon (work) and nomos (law). The program presented here concentrates on the physical fit between the job and the worker. The goal of a successful ergonomic program is proactive prevention and early identification of the risk factors that lead to MSDs. This involves recognition and an understanding of the causes of musculoskeletal disorders and the implementation of changes which will eliminate these causes. When the demands of a job exceed human capacities, musculoskeletal disorders can occur. Musculoskeletal disorders (MSDs), sometimes referred to as repetitive strain injuries or repetitive motion injuries, are disorders of the muscles, skeleton, and nervous system that occur in the upper or lower extremities and the lower back. MSDs involve damage to the tendons, tendon sheaths, synovial lubrication of the tendon sheaths, and the related bones, muscles and nerves of the hands, wrists, elbows, shoulders, neck, and back. The most common disorders include carpal tunnel syndrome, tennis elbow, tendonitis, tenosynovitis, DeQuervain s Disease, and lower back pain. Musculoskeletal disorders are not caused by a single incident, such as a fall or being struck by an object. MSDs develop after repeated, or chronic, exposure to ergonomic risk factors over a period of time. The three primary risk factors that often lead to MSDs are: FORCE, REPETITION and POSTURE. What is Ergonomics? Goal of Ergonomics What are MSDs? Causes of MSDs Examples of these include: Forceful Exertions (Primarily with the hands, including pinch grips) Excessive Repetition or Prolonged Activities Awkward Body Mechanics or Prolonged Static Postures Continued Physical Contact with Work Surfaces Environmental conditions such as heat, cold, or lighting can also influence risk factors which lead to MSDs Why is there a need for ergonomics? Technological changes in the work force demand that people perform a limited range of job tasks at a much more rapid pace than ever before, and often for longer periods of time. This can lead to the incidence of repetitive motion injuries, or MSDs. The effects of MSDs in the work place range from the rising incidence of illnesses and injuries and a decrease in productivity, to higher workers compensation costs, lost work time, and more. Need for Ergonomics Effects of MSDs Summit Training Source, Inc. 3

5 Benefits of Ergonomics Since employees are a company s most important asset, ergonomic principles should be applied to every work station and job task performed. They should also be applied to the tools used and environmental conditions such as lighting. Ergonomic principles can also be applied to new designs and to redesigns of workstations and workplaces. Benefits of Ergonomics The benefits of a successful ergonomic program include a reduction in workers compensation costs and musculoskeletal disorders, a safe and healthy work environment, increased productivity and quality control, increased employee morale, and decreased absenteeism and turnover. Reduced incidence of MSDs Increased productivity and quality Safe and healthy work environment Ergonomics Program Lower workers compensation costs Decreased absenteeism and turnover Increased employee morale Ergonomics is an ongoing process that requires commitment and participation from everyone. The mission of an Ergonomics Team is proactive prevention of MSDs through early identification, analysis, and control. For example, part of a commitment to ergonomic principles in the workplace involves the following proactive countermeasures: Five Elements of a Proactive Ergonomic Program Safety Activity/Ergonomic Teams Work Site Analysis Job Hazard Prevention and Control Medical Management Training and Education Summit Training Source, Inc. 4

6 Program Components Safety Activities/Ergonomics Team The Ergonomics Team should be part of the Safety Activity Task Group and meet monthly to review accident reports and OSHA Injury and Illness Logs. The team is responsible for identifying and correcting ergonomic hazards in the work place. Their goal is to identify causes of accidents and trends related to ergonomic hazards. Team members monitor problems that have been identified and establish plans for corrective action. Work Site Analysis The purpose of Work Site Analysis is to identify and eliminate ergonomic stressors which can lead to MSDs and manual material handling (MMH) injuries. This is done by analyzing the tasks required for a job and measuring postural deviations. From this analysis, patterns may emerge and comparisons can be made between task elements and risk factors. The Work Site Analysis program provides procedures for identifying and controlling tools, methods, equipment, and conditions that are potential risk factors. The objectives of a Work Site Analysis are to recognize, identify, and correct ergonomic hazards. Review and Analyze Injury and Illness Records Identify Work Positions that Need a Quantitative Analysis A Work Site Analysis involves the following steps: Review and analyze injury and illness records. This includes medical, safety, and insurance records, including the OSHA Injury and Illness Log and information gathered from the medical management program. The objective is to locate evidence of musculoskeletal disorders. This is done by identifying and analyzing any trends in the work place. Systematically identify those jobs which need a quantitative analysis of ergonomic hazards. This is done by completing baseline screening surveys to identify which work operations need to have an ergonomic hazard analysis. This baseline survey consists of a Body Discomfort Chart and an Ergonomic Checklist completed by the operator that would identify work positions that put workers at risk of developing MSDs. The results should be applied to all planned, new and modified facilities, processes, materials, and equipment to ensure that work place changes can be made which reduce or eliminate ergonomic hazards. Remember, making changes at the design stage is much less expensive than subsequent redesign. An analysis of ergonomic hazards should be performed routinely and documented by a qualified person. This is a before and after evaluation which provides quantitative data that is used to compare the original operations to the modified jobs. There are two types of Job Hazard Analysis : one for operations which have the potential for MSDs to occur and one for operations with a risk of developing manual material handling injuries. Periodic surveys of the work site should be conducted at least annually, or whenever operations change, to identify new risk factors, and to assess the effects of changes in the work processes. Analyze Ergonomic Hazards Conduct Periodic Surveys of the Worksite Summit Training Source, Inc. 5

7 Job Hazard Prevention and Control Once ergonomic hazards are identified through the work site analysis, the next step is to design measures to prevent or control these hazards. Job Hazard Prevention and Control is an action plan developed from the work site analysis. It s purpose is to minimize or eliminate the risk factors. Measures to prevent or control ergonomic hazards are: Engineering Controls -- such as work station design, design of work methods, and tool design. Work Practice Controls -- such as proper work techniques, new employee conditioning periods, monitoring all levels of operation, and making adjustments and modifications. Administrative Controls -- that reduce the duration, frequency, and severity of exposures to ergonomic stressors. These would include providing rest pauses to relieve fatigued muscle-tendon groups, using job rotation, an effective housekeeping program, and other methods of control. Personal Protective Equipment -- should be selected with ergonomic stressors in mind. Proper fit is essential. PPE should accommodate the physical requirements of workers and the job and should not contribute to extreme postures and excessive forces. Engineering Controls Work Practice Controls Administrative Controls Personal Protective Equipment Medical Management An effective medical management program is essential for early identification and treatment. The key is early identification and treatment of MSD symptoms and the prevention of future occurrences. An effective medical management program includes health care providers who are part of the ergonomic team, interacting, and exchanging information in order to prevent and properly treat MSDs. Medical management conducts periodic, systematic work place walk-throughs by medical staff to remain knowledgeable about operations and work practices. As part of the ergonomics team, medical staff are continuously involved in identifying risk factors for MSDs in the work place. They develop and initiate surveys to measure employee awareness of work-related disorders and identify areas or jobs where potential MSD problems exist. Medical management may also be involved in the training and education of all employees concerning the different types of MSDs, their causes and means of prevention, early symptoms, and treatment. The medical management program should address the following issues: Injury and Illness Recordkeeping Early Recognition and Reporting -Employee baseline surveys -Education and training on symptoms Summit Training Source, Inc. 6

8 Systematic Evaluation and Referral -Exam procedures for workers with symptoms -Criteria for referring workers to outside medical experts Conservative Treatment -Focus on prevention -Treatment developed by an authorized physician Conservative Return to Work Policy -Adequate recovery time from treatment -Provisions for modified/alternative work Systematic Monitoring -Follow-up on reports of minor symptoms -Monitor employees following treatment -Follow-up on return to work break-in period Site Evaluations -Conduct periodic work place walk-throughs -Document risk factors recognized and actions taken to correct identified problems -Initiate followup Adequate Staffing and Facilities Training and Education The purpose of training and education is (1) to create an awareness and respect for the causes of musculoskeletal disorders and (2) early recognition of the symptoms. Education and training are necessary to ensure that employees are informed about the ergonomic hazards they may be exposed to and can actively participate in their own protection. Training allows managers, supervisors, and employees to understand ergonomic hazards, their medical consequences, and their prevention and control. A training program must include the following individuals: All Affected Employees Engineers and Maintenance Personnel Supervisors Managers Health Care Providers Purchasing Departments Ergonomics training should be presented at a level of understanding appropriate for the individuals being trained. It should provide an overview of the potential risk of illnesses and injuries, their causes and early symptoms, the means of prevention, and treatment. The program should also provide a means for evaluating its effectiveness. This could be accomplished with employee interviews, testing, and observing work practices. The Ergonomics Rule Flow Chart, at the end of this section, gives a quick reference for the decision process and trigger points regarding OSHA standard Please visit Summit's web site at for more information and a downloadable PDF file of the Ergonomics Program Standard. Summit Training Source, Inc. 7

9 ERGONOMICS RULE FLOW CHART (RELEVANT STANDARD PARAGRAPH SHOWN IN PARENTHESES) (b) EMPLOYER DETERMINES WHETHER STANDARD APPLIES TO HIS OR HER BUSINESS AGRICULTURE CONSTRUCTION MARITIME RAILROADS STANDARD DOES NOT APPLY GENERAL INDUSTRY EMPLOYER HAS ERGONOMICS PROGRAM EMPLOYER DOES NOT HAVE ERGONOMICS PROGRAM (c) EMPLOYER DETERMINES WHETHER THE PROGRAM MEETS THE REQUIREMENTS OF PARAGRAPH(c) No Yes (d) EMPLOYER PROVIDES EMPLOYEES WITH BASIC INFORMATION ABOUT MSDs AND THE STANDARD EMPLOYER CONTINUES TO OPERATE HIS OR HER ERGONOMICS PROGRAM (e) EMPLOYEE REPORTS MSD OR MSD SIGNS & SYMPTOMS Summit Training Source, Inc a

10 (e) EMPLOYER DETERMINES IF IT IS AN MSD INCIDENT No NO FURTHER ACTION REQUIRED Yes (e) & (f) EMPLOYER DETERMINES IF THE JOB INVOLVES EXPOSURE TO RELEVANT RISK FACTORS AT LEVELS IN THE BASIC SCREENING TOOL No NO FURTHER ACTION REQUIRED Yes (p) (r) EMPLOYER IMPLEMENTS MSD MANAGEMENT PROCESS (g) (q) WORK RESTRICTION PROTECTION CONTENTS OF HEALTH CARE PROFESSIONAL'S OPINION Yes MUST DO BOTH (h) (s) REQUEST FOR SECOND OPINION Yes (g) EMPLOYER IMPLEMENTS PROGRAM (h) (j) MANAGEMENT LEADERSHIP JOB HAZARD ANALYSIS (i) (t) EMPLOYEE PARTICIPATION TRAINING QUICK FIX NOT SUCCESSFUL OR EMPLOYER NOT ELIGIBLE (o) EMPLOYER MAY USE QUICK FIX IF ELIGIBLE TYPES OF CONTROLS (l) QUICK FIX SUCCESSFUL Summit Training Source, Inc EMPLOYER MAINTAINS CONTROLS AND TRAINING RELATED TO CONTROLS 7b

11 (j) (g) EMPLOYER CONDUCTS JOB HAZARD ANALYSIS NO MSD HAZARDS EMPLOYER MAINTAINS PROGRAM MSD HAZARDS IDENTIFIED (l) & (m) EMPLOYER IMPLEMENTS CONTROLS MSD HAZARDS REDUCED TO EXTENT FEASIBLE MSD HAZARDS CONTROLLED, OR REDUCED BELOW APPENDIX D LEVELS (k) EMPLOYER PERIODICALLY CHECKS IF ADDED CONTROLS WOULD CONTROL OR REDUCE MSD HAZARDS, AND, IF SO, IMPLEMENTS THE CONTROLS (k) JOB HAS BEEN CONTROLLED RISK FACTORS REDUCED BELOW LEVELS IN BASIC SCREENING TOOL (y) EMPLOYER MAY DISCONTINUE PROGRAM EXCEPT FOR MAINTAINING CONTROLS AND TRAINING RELATED TO CONTROLS (u) EMPLOYER EVALUATES PROGRAM Note: Employers with 11 or more employees must keep records as specified in paragraph (v). Summit Training Source, Inc c

12 Ergonomic Qualitative Analysis Purpose of Qualitative Analysis Ergonomic Checklist Function Administering the Ergonomic Checklist When a Job Hazard Analysis is Warranted Ergonomic Checklist Body Discomfort Chart Function Times to Conduct the Survey Procedures for Preventing Bias Body Discomfort Chart Analyzing the Data Interpreting the Data Summit Training Source, Inc. 8

13 An Ergonomic Qualitative Analysis is a baseline survey that serves as a screening device to determine if a job hazard analysis needs to be performed. The two tools for conducting a qualitative analysis are an Ergonomic Checklist and a Body Discomfort Chart. In most cases, the Ergonomic Checklist and the Body Discomfort Chart will be administered by the supervisor of the specific work area being analyzed. Because this is a controlled analysis involving interaction with people, it is important that the administration be consistent to avoid influencing the data collection. Ergonomic Checklist The Ergonomic Checklist is always used with the Body Discomfort Chart to identify jobs that may possess the potential for MSDs or manual material handling (MMH) risk factors. It is comprised of two sections: a generic task/work place checklist and another for MMH tasks. Employees should complete the section that is appropriate to their job. The checklist is comprised of a series of YES or NO questions. It should be given to all employees on the particular job being studied. If you are administering the checklist, you should give a brief introduction to the employees who will be completing the form. As with any survey involving human opinion, there is potential to influence the data being collected. When administering the survey for the first time, give a brief explanation for the purpose of the survey but try not to answer any direct questions. Purpose of Qualitative Analysis It is important to avoid influencing the data collection Function of the Ergonomic Checklist Administering the Ergonomic Checklist Sample Introduction: The Ergonomic Team is conducting a survey of different job functions in the facility. A part of this survey is an Ergonomic Checklist. Please answer the questions with a YES or NO. Thank You. The person who administers the checklist may need to assist an employee who has a learning disability or who does not understand English. When this is the situation, it is important not to influence the data being collected by the inflection of your voice or the phrasing of the questions. After the Ergonomic Checklists are completed, the data may indicate the need for a Job Hazard Analysis if the following occurs: Five or more questions are answered YES by 25 percent of the participating employees in the generic task/work place checklist. Three or more questions are answered YES by 25 percent of the employees completing the Manual Material Handling Checklist. When a Job Hazard Analysis is Needed Summit Training Source, Inc. 9

14 Employee ID# Department Job Date/Time Task/Work Place Ergonomic Checklist YES NO Does the task require frequent extreme motions of the back, neck, shoulders or wrists? Examples include: reaching above shoulder level, reaching behind the body, continually bending or twisting the back, neck, shoulders, or wrists. Are the elbows raised and unsupported for an extended period of the time? Do the hands/wrists/arms come in contact with any sharp, or non-rounded, edges on the table/machinery? Does the task require gripping with the fingers? Do the knee/foot controls require force? Answer if task is sit-down: Is leg clearance restricted? Are the foot/legs unsupported or your thighs sloping down in the front (there is no footrest or it is not able to be used)? Does the chair or table restrict the thighs? Is the back unsupported (no backrest or not being used)? Is the chair height fixed (not adjustable or only adjustable using tools)? Answer if task is stand-up: Does the knee/foot control require you to support your weight on one foot for much of the time? Is the standing surface hard and unsupported (no mat)? Is the work surface height fixed (not adjustable)? Answer if task requires frequent use of hand tools: Does tool require wrist/hand bending or twisting? Does tool vibrate? Can tool only be used with one hand? Does tool handle end in palm? (continued) Summit Training Source, Inc

15 Does tool handle have any sharp, or non-rounded, edges or corners? Does tool operation involve only 2 or 3 fingers? Does tool operation require continuous or high force? Is tool continually held in the hand? Environment: Is the total lighting level inadequate at your work place? Is there glare, from surface reflections or other light sources, which affect your ability to see your work? Is there any vibration at your work place? Is the temperature uncomfortably hot or cold in the winter? Is the temperature uncomfortably hot or cold in the summer? YES NO Summit Training Source, Inc

16 Employee ID# Department Job Date/Time Manual Material Handling Tasks Answer if the task involves lifting/lowering or pushing/pulling: Does the task require you to perform more than 5 lifts/min? Are any of the loads unbalanced? Does the task require you to lift items over your head? Does the task require you to lift items off the floor? Does the task require you to reach out with your arms while lifting/lowering or pushing/pulling? Does the task require you to twist or bend while lifting/lowering or pushing/pulling? Is the floor wet or slippery? Is the floor in poor condition (surface cracks, etc.)? Is the area obstructed so that you have to modify your lifting/lowering or pushing/pulling postures? Is protective clothing ever unavailable when needed? Ergonomic Checklist Is the temperature uncomfortably hot or cold in the winter? Is the temperature uncomfortably hot or cold in the summer? YES NO Summit Training Source, Inc

17 Body Discomfort Chart The Body Discomfort Chart is another tool used to determine if a Job Hazard Analysis should be conducted. It is also used after ergonomic modifications have been made to a work place to provide a before and after comparison. These two purposes are accomplished by recording worker discomfort experienced throughout the day over a continuous 5-day work period. Like the Ergonomic Checklist, the Body Discomfort Chart should be given to all operators on the particular job being studied. New hires and/or recent trainees should not be included in the survey. Function of the Body Discomfort Chart The Body Discomfort Chart includes a generic human form with different body parts identified. The operator indicates the level of pain they are experiencing at the specific time for each body part. The chart uses a 0-5 numeral rating with a 0 for no pain and a 5 for severe pain. The Body Discomfort Chart is located on page 16 of this manual. When to Conduct the Survey The survey should be performed four times a day for a 5-day period. Recommended times for conducting the survey include: Minutes 11 Before Morning 1 Break 10 2 Just Before Lunch 9 3 Before Afternoon Break 8 4 When to Conduct the Body Discomfort Chart At End of Day, 7 Before Clean-up 5 or End-of-Day Activities 6 When the Body Discomfort Chart is administered after ergonomic solutions have been implemented, the survey should be conducted at least two weeks -- but no longer than four weeks -- after changes have been implemented. Summit Training Source, Inc. 13

18 Procedures for Preventing Biased Data The potential to influence the data being collected while administering the Body Discomfort Chart is just as significant as it is when administering the Ergonomic Checklist. The following procedures will help prevent influencing the data: Label a new form for each administration of the survey for each operator. The form should include the subject number instead of the person s name, the date, the time the survey was administered, and the job being surveyed. Procedures for Administering the Body Discomfort Chart Use a new form each time the survey is administered. This is important for two reasons: (1) It requires the participant to analyze the degree of discomfort each time the survey is taken, instead of just saying the discomfort is the same. (2) It also serves as a reminder to the analyst to collect the data. Avoid showing the operator their previous responses. This helps maintain consistency and validity in the survey. Never try to influence the response with comments such as Are you sure it is hurting that bad? or How is the pain in your legs today? Use a consistent and neutral approach. When administering the survey for the first time, provide a brief explanation for the purpose of the survey but try not to answer direct questions. Inform the operators that you are collecting the data which will be analyzed by the Ergonomic Task Force when the survey is completed. Do not try to keep running totals while the survey is being conducted. This may bias the data collection. Avoid the urge to see how it is going and leave all data analysis until the end of the survey. Summit Training Source, Inc. 14

19 BODY DISCOMFORT CHART PART A Date Employee Number Plant Department Job Name Supervisor Hours Worked This Week Time on This Job (Years and Months) List other jobs you have done in the last year: Department Job Name Time on This Job (Years and Months) Summit Training Source, Inc

20 BODY DISCOMFORT CHART PART B Job ID # Time Using an appropriate number from below, fill in those areas where you feel discomfort: No Severe Pain Moderate Pain Pain Eyes Right Shoulder Left Shoulder Left Shoulder Right Shoulder Right Arm Abdominal Left Arm Upper Back Middle Back Lower Back Right Wrist Left Wrist Buttocks Right Hand Left Hand Left Leg Right Leg Right Knee Left Knee Left Calf Right Calf Right Ankle Left Ankle Right Foot Left Foot FRONT BACK Please comment on what you think would make you more comfortable. Summit Training Source, Inc

21 Analyzing the Data When the survey is completed and the data is compiled, it is then analyzed. If the Body Discomfort Chart has been conducted as an initial or baseline screening, the data will need to be examined to determine if 25 percent or more of the sample indicates a specific body part as a 3 or higher. If this is the case, a Job Hazard Analysis may be necessary. Analyzing the Data If the survey has been conducted as a before and after analysis, the data should be analyzed for individual body parts for one operator, multiple operators, or overall discomfort data. Analyzing Individual Body Parts for One Employee To analyze individual body parts for one employee, total the ratings for each time period, including any zeros. Divide the totals by the number of readings to calculate an average. For example, if the survey was conducted four times in one day, then the number of readings is 4. If an individual s totals on those surveys were 2, 3, 3 and 4, then add those numbers together and divide by 4. Analyzing Individual Body Parts for One Operator = 12 (total) 12 (total) 4 (number of readings) = 3 (average) When a Reading is Missing If a reading is missing from the survey, do not calculate it into the average. For example, if the survey was conducted four times in one day, but the individual missed one of the surveys, the number of readings is 3. Add the totals from those three surveys together and divide by 3. If a Reading is Missed = 8 (total) 8 (total) 3 (number of readings) = 2.66 (average) If more than one or two readings are missing, the validity of the survey will be in jeopardy. Multiple Employees and Overall Discomfort Data The data can be compiled and analyzed in the same manner for multiple employees and overall discomfort data. To calculate overall discomfort data, total the sum of all body parts for all days at the specific time period and then divide by the total number of scores in the sum. For example, if the ratings total is 10, then you would divide that number by 25, since there are 25 different readings. Calculating Overall Discomfort Summit Training Source, Inc. 17

22 The information can then be analyzed to see if there is an increase in discomfort throughout the day or discomfort experienced in specific body parts. The data gathered from the Ergonomic Checklist and Body Discomfort Charts will provide valuable information for determining whether a Job Hazard Analysis is warranted. It also serves to determine if ergonomic changes have been effective and should be implemented throughout the facility. Exercises 1. Analyzing Individual Body Parts for One Employee The Body Discomfort Chart was administered to an operator four times a day for five days. Your R. Shoulder Mon. Tues. Wed. Thur. Fri. objective is to determine the average body discomfort for the week for the right shoulder at the 11:30 am survey time. Using the ratings given in the 9:30am 11:30am chart, what is the total of the 2:30pm ratings for the 11:30am time period and the average discomfort level at 11:30am for the week? 4:30pm Total Average 2. Analyzing Individual Body Parts for Multiple Employees The Body Discomfort Chart was administered to four employees, four times today. Your objective is to determine the employees overall discomfort in the left wrist for today. Using the ratings for the left wrist given below, what is the total of the readings and the average discomfort for the day? Operator 1: 1, 1, 2, 3 Operator 2: 1, 2, 2, 2 Operator 3: 2, 2, 1, 3 Operator 4: 2, 2, 3, 3 Total Average 3. Analyzing All Body Parts for Multiple Employees The Body Discomfort Chart was administered to three employees just before lunch today. Your objective is to determine the overall body discomfort for this time period. Using the overall body discomfort readings given below for these employees, what is the total of the readings and the overall body discomfort average? Operator 1: 13 Operator 2: 12 Operator 3: 11 Operator 4: 14 Total Average Summit Training Source, Inc. 18

23 Interpreting the Data Once the data has been gathered and analyzed, it must then be interpreted. While analyzing the data involves determining areas of discomfort, interpreting the data involves determining the causes of discomfort. Interpreting the Data Look for patterns of discomfort that may occur in the data. They can help you to determine if discomfort is due to work station design or posture. For example, does data indicate discomfort that increases as the day goes on or is the level of discomfort continuous? Discomfort that increases due to gradual fatigue could be caused by posture or work station design could be the cause. Items to consider include.... Is the employee performing the task properly? Does the work station fit the employee? Is task design a factor? It is important to note whether discomfort is experienced by one or more employees who perform the same task. This can provide clues as to whether the discomfort is caused by posture or work station design. For example, if only one employee experiences discomfort in the right shoulder while other employees performing the same function do not, it is possible that the employee s discomfort is due to his/her improper posture or the employee is performing the job task in an incorrect manner. It is also possible that size could be a factor. For example, if the task requires employees to reach a high shelf, does this particular employee have difficulty doing so due to his/her size? If the other employees also experienced discomfort in the right shoulder, then work station or task design could be a factor. If enough employees indicate a discomfort level of 3 or more on the Body Discomfort Chart, then a Job Hazard Analysis will need to be conducted to validate the findings and pinpoint where postural deviation is occurring. When the data has been gathered after ergonomic solutions have been implemented, it must be interpreted to determine if further changes must be made. It is possible for discomfort levels to increase after a change has been made to the work environment. This could be due to a change in posture and may decrease after a few weeks. If discomfort does not decrease, then other changes may need to be made. Care must be taken not to make hasty conclusions when interpreting the data. Interpretation involves a deliberate process in which all possible causes must be considered. Answers to Exercises 1. Total = 9; Average = Total = 32; Average = 2 3. Total = 50; Average = 12.5 Summit Training Source, Inc. 19

24 Job Hazard Analysis Objective Selecting the Job to Analyze Choosing the Operator Ergonomic Job Hazard Analysis Chart Administrative Detail Additional Risk Factors Task Elements Grips Postural Data Using Videotape Videotaping Techniques Recording Postural Data Measuring Postural Deviation Wrist Extension/Flexion Wrist Radial/Ulnar Back Rotation Back Lateral Bend Back Extension/Flexion Neck Rotation Neck Lateral Bend Neck Extension/Flexion Shoulder Abduction/Adduction Shoulder Extension/Flexion Ergonomic Job Hazard Analysis Chart Summit Training Source, Inc. 20

25 A Job Hazard Analysis is a scientific means to identify ergonomic stress factors that lead to musculoskeletal disorders. As part of the work site analysis, it should be performed by a qualified person for job tasks with ergonomic risk factors. The objective of a job hazard analysis is to identify ergonomic stress factors and find solutions. Objective of Job Hazard Analysis The first step is selecting the job to analyze. Leading indicators are jobs that have a high frequency rate on the OSHA Injury and Illness Log or those that meet the criteria established with the Ergonomic Checklist and Body Discomfort Charts. Once you have determined the operation to analyze, choose the operator you will observe. The choice of operator is very important. An experienced operator who uses proper methods and has no visible bad habits should be selected. Selecting the Job to Analyze Choosing the Operator Your main tool in conducting the Job Hazard Analysis is the Ergonomic Job Hazard Analysis Chart, located on page 38 of this manual. This chart contains five primary areas of information: Administrative Detail Additional Risk Factors Task Elements Grips Postural Data Summit Training Source, Inc. 21

26 Administrative Detail Additional Risk Factors Date Completed by Plant Job Title/Desc. ERGONOMIC JOB HAZARD ANALYSIS CHART Average daily hours performing task Number and duration of breaks (including lunch) Daily units produced by operator # of OSHA recordable injuries (past 12 months) # of employees doing this job ADDITIONAL RISK FACTORS 1. Is vibration a factor? 2. Is inadequate lighting/glare a factor? 3. Are there sharp edges on tables/machinery? 4. Is proper leg clearance impaired? 5. Does chair or table impinge thigh? 6. Do foot controls require excessive force? 7. Are elbows raised and unsupported? 8. Is excessive twisting of forearm/hand involved? Yes No Task Elements Grips TASK ELEMENTS COLUMN TOTAL GRIPS Pinch/Finger Hand/Power Low Force = 1 High Force = 1 High Force = 2 Only L R L R COLUMN ZONE (a) (b) (c) (d) TOTAL WRIST BACK NECK SHOULDER Flexion/ Radial/Ulnar Flexion/ Rotation Lateral Flexion/ Rotation Lateral Flexion/ Abduction/ Extension Deviation Extens Bend Extens Bend Extension Adduction L R L R L R L R (e) (f) (g) (h) (i) (j) (k) (l) (m) (n) (o) (p) (q) (r) WRIST BACK NECK SHOULDER s s s s Flex Rot Rot Flex Ext Lat Lat Ext Radial Flex Flex Abduct Ulnar Ext Ext Adduct LEFT GRIP INDEX (a) + (c) = RIGHT GRIP INDEX (b) + (d) = LEFT WRIST INDEX (e) + (g) = RIGHT WRIST INDEX (f) + (h) = BACK INDEX (i) + (l) + (k) = NECK INDEX (l) + (m) + (n) = LEFT SHOULDER INDEX (o) + (q) = RIGHT SHOULDER INDEX (p) + (r) = LEFT WRIST EXPOSURE (Left Grip Index + Left Wrist Index) x Daily Units = RIGHT WRIST EXPOSURE (Right Grip Index + Right Wrist Index) x Daily Units = Postural Data Administrative Detail Administrative detail is included in the upper left hand section of the chart. It includes information such as the date, average daily hours performing the task, number and duration of breaks, number of units produced by the operator, number of OSHA recordable injuries, and number of employees doing the particular job. This information should be completed by the analyst so the operation can be effectively tracked. Administrative Detail Date Completed by Plant Job Title/Desc. Average daily hours performing task Number and duration of breaks (including lunch) Daily units produced by operator # of OSHA recordable injuries (past 12 months) # of employees doing this job Summit Training Source, Inc. 22

27 Additional Risk Factors The section on additional risk factors is located in the upper right hand section of the chart. In this section, check the YES box for each risk factor that is present in the operation. You can determine this through observation on the floor or during the video analysis. Additional Risk Factors ADDITIONAL RISK FACTORS 1. Is vibration a factor? 2. Is inadequate lighting/glare a factor? 3. Are there sharp edges on tables/machinery? 4. Is proper leg clearance impaired? 5. Does chair or table impinge thigh? 6. Do foot controls require excessive force? 7. Are elbows raised and unsupported? 8. Is excessive twisting of forearm/hand involved? Yes No Vibration Lighting Sharp Edges Leg Clearance Thigh Impingement Elbows Raised or Unsupported Foot Controls Which Require Excessive Force Excessive Twisting of the Forearm and/or Hand Task Elements The task elements are the different elements required to complete the task. Each element for the task being analyzed is listed in the left hand column labeled Task Elements. It is important to make sure that each task element is listed in this column so that the proper data can be collected. Task elements can be identified by observing the job task on video or obtaining the time motion sheets used by engineering. The level of detail for the task elements needs to be thorough enough to capture all extreme postures. A sleeve set task can be broken down into eight different elements which could be listed in the following manner: Task Elements Sources for Identifying Task Elements Summit Training Source, Inc. 23

28 Task Elements Positions Sleeve Opening of the Body 2. Matches Sleeve to the Body Places Under Sewing Foot 4. Aligns Sleeve to Body Sleeve Sewn to Body 6. Repositions Body and Matches Other Sleeve Sleeve and Body Moved to Needle 8. Sleeve and Body Aligned and Sewn Summit Training Source, Inc. 24

29 Grips Pinch/Finger Low Force = 1 High Force = 2 L R 1 1 GRIPS Hand/Power High Force = 1 Only L R For each task element, indicate the hand grip for the left and right hand. The tip, pulp, lateral, and finger press are considered pinch grips. A 1 or 2 should be indicated for low and high force, respectively. The power grip is more efficient and is rated as a 1. This information can be obtained through observation or by asking the operator. Grips Power Grip The power grip is a more efficient grip, and is rated as a 1. Power Grip Pinch Grips These are considered pinch grips. A 1 or 2 should be indicated for low and high force, respectively. Tip Lateral Pulp Finger Press Pinch Grips Summit Training Source, Inc. 25

30 Postural Data The fifth area of the Ergonomic Job Hazard Analysis Chart is postural data for the wrist, back, neck, and shoulders. Measurements are taken of each joint for each task element identified. The angle in degrees is recorded along with the zone assigned from the table located at the bottom of the chart. Postural Data Examples of postural deviation and measurement points are provided for each respective joint beginning on page 31. For example, if a task element indicated a flexion of the back of 25, then 25 would be entered in the degree column and the corresponding zone would be entered below that number. To find the correct zone for 25 back flexion, use the section of the table at the bottom of the chart for the BACK. Find the row labeled Flex. for flexion and go across until you locate the column of numbers that includes 25. Since 25 is included in the numbers listed in column one, then the zone is 1. WRIST BACK Flexion/ Extension Radial/Ulnar Deviation Flexion/ Extens Rotation Lateral Bend L R L R 25 1 COLUMN ZONE TOTAL (e) (f) (g) (h) (i) (j) (k) A back flexion of 25 would be located in 1. BACK s Rot. Lat. Flex. Ext s Rot. Lat. Flex. Ext. BACK NECK s Rot Lat Flex Ext Summit Training Source, Inc. 26

31 Using Videotape The most effective and accurate way to measure postural deviation is to videotape the operation. Several cycles of the operation should be videotaped from the following angles: A Direct Front View A Direct Back View Videotape Postural Deviation from Many Angles A Direct View From the Left Side A Direct View From the Right Side A Front View, Half- Way Between the Front and Side, with the Camera Higher than the Operator s Head The objective of videotaping the operation from five different positions is to ensure that task elements are clearly visible. Some postural deviations are better visible and more easily measurable from one angle than another. At least four complete cycles should be videotaped from each angle, capturing the operator from head to toe. Videotaping more cycles using close-ups of the upper extremities can make wrist measurements easier to gather. Videotaping Techniques Techniques you can use to improve the quality of the videotaping include the following: Hold the camera as steady as possible or use a tripod. Objective of Videotaping from Many Angles Videotape at Least Four Cycles of an Operation Videotaping Techniques Make sure you have a clear, unobstructed view of the operator -- without altering the normal workstation design and layout. Use a vertical reference point such as a support post or other object in your framing to ensure accurate measurements of angles with respect to the vertical reference. Properly frame the operator so that all movements are captured on the videotape-- but the operator should not appear small. Make sure the videotape has some form of identification which notes the time, date, operator, and job function. Concentrate on the operator, not on the part being processed. Summit Training Source, Inc. 27

32 Procedures for Recording Postural Data When viewing the videotape, record the angles for the most extreme postural deviation for each task element. A postural deviation is any movement that places the body out of the neutral position. Postural deviation can be measured by freezing the video and using a protractor to calculate the angle. Measure postural deviations for each joint directly off the monitor. Always use the camera angle that provides a direct view of each postural deviation. Measuring Postural Deviation After freezing the videotape, measure the angles using specific reference points and a protractor. Record the angle in degrees in the proper column of the Job Hazard Analysis Chart along with the corresponding zone from the table at the bottom of the chart. For example, if an operator had a back flexion of 25, then you would enter 25/F in the degree column. The F indicates flexion. Recording Postural Deviation on the Job Hazard Analysis Chart Using the table at the bottom of the chart, you would then determine the zone for the degree of flexion. A back flexion of 25 is zone 1. A 1 is recorded in the zone column under back flexion for the first element. Flexion/ Extension WRIST Radial/Ulnar Deviation L R L R Flexion/ Extens 25/F 1 BACK Rotation Lateral Bend BACK s Rot. Lat. Flex. Ext Summit Training Source, Inc. 28

33 Once the angles have been recorded for each task element listed, total the zones and record the number for each column, A through R, located at the end of the columns where degrees and zones of deviation are entered. Add the appropriate columns indicated in the boxes at the bottom of the chart to calculate the indexes. The purpose of the Job Hazard Analysis is to validate discomfort data from the Body Discomfort Chart and Ergonomic Checklist. The data collected will serve as a guide in developing solutions that lower zone values. The areas of concern are those task elements where deviation occurs. With data collected from the JHA we can focus on those areas and determine whether the cause is work station, task design, or posture. From the analysis, patterns will emerge and comparisons can be made between task elements and risk factors. For example, an employee who performs very detailed work and has extreme deviation for the back may be working under inadequate lighting which causes the employee to slouch forward to better see his/her work. Situations where task elements indicate risk factors but little or no discomfort will need to be examined further. Summit Training Source, Inc. 29

34 Measuring Postural Deviation A postural deviation is any movement that places the body out of the neutral position. The neutral position is the natural posture that puts the least amount of stress on the body: Proper Posture The neck is straight, aligned with the back. The back maintains the natural S shape of the spinal column. Proper Posture The shoulders are relaxed and perpendicular to the spine. The wrists are a natural extension of the forearms. Postural Deviation Examples of postural deviation include the following: Flexion or Extension of the Wrists, Back, Neck, and Shoulders. Types of Postural Deviation Rotation or Lateral Bending of the Back and Neck. Abduction or Adduction of the Shoulders. Radial and Ulnar Deviation of the Wrists. Examples of postural deviation and correct measurement points are provided on pages to assist you in properly recording postural data. Summit Training Source, Inc. 30

35 Wrist Extension Extend a line from the forearm through the center of the wrist. Draw a second line from the center of the wrist through the extreme position of the second knuckle of the hand. Wrist Extension Wrist Flexion The best camera angle for measurements are the front, side, or half view. Wrist Flexion Extend a line from the center of the forearm through the center of the wrist. Using the center of the wrist as an origin, draw a second line through the second knuckle of the hand. Wrist Radial Wrist Radial This angle is best measured from the front, side, or half view camera positions. Wrist Ulnar Wrist Ulnar Summit Training Source, Inc. 31

36 Back Rotation Draw a vertical line through the center of the shoulders and head. Using the center of the head as the origin, draw a second line through the center of the respective shoulder. Back Rotation This angle is best measured from a top view. Left Right Back Lateral Bend Draw a vertical line through the center of the head and the lower back. Use the lower back as an origin point to draw the second line through the center of the head at its extreme deviation point. Back Lateral Bend Left This angle is measured from the front or back. Right Summit Training Source, Inc. 32

37 Draw a vertical line from the lower back through the center of the shoulders. Originating from the lower back, draw the second line through the extreme position of the shoulders. Back Flexion Back Extension This angle is best measured from a side view. Back Flexion Back Extension Neck Rotation Draw a horizontal line through the nose and the center of the head. Use the center of the head as the origin point to draw a second line at the extreme position through the center of the nose. Neck Rotation This angle is best measured from a top view. Left Right Summit Training Source, Inc. 33

38 Neck Lateral Bend Draw a vertical line through the center of the head. Use the bottom of the neck as the origin point for the second line to be drawn through the center of the head at its extreme position. Neck Lateral Bend This angle is measured from the front or back view. Left Right Draw a vertical line from the shoulders through the center of the head. At its extreme position, draw a second line through the center of the head using the base of the neck as the origin point. Neck Extension Neck Flexion Neck Extension This angle is measured from a side view. Neck Flexion Summit Training Source, Inc. 34

39 Draw a vertical line through the center of the shoulder. Using the center of the shoulder as the origin point, draw a second line through the extreme position of the upper arm. This angle is measured from the front or back. Shoulder Abduction Shoulder Adduction Shoulder Abduction Shoulder Adduction Draw a vertical line from the center of the shoulder as the origin. Draw the second line through the extreme center position of the upper arm. This angle is measured from a side view. Shoulder Extension Shoulder Flexion Shoulder Extension Shoulder Flexion Summit Training Source, Inc. 35

40 Measurement Exercises Using a protractor and a pen or pencil, determine the degree of postural deviation. Use the guidelines for measuring postural deviation provided on pages Use the Job Hazard Analysis Chart on page 28 to determine the proper zone. Type of Postural Deviation of Deviation Type of Postural Deviation of Deviation Type of Postural Deviation of Deviation Summit Training Source, Inc

41 Answers to Measurement Exercises Type of Postural Deviation Back Flexion 37 of Deviation 37 F 2 Type of Postural Deviation Wrist Extension 59º of Deviation 60 E 3 Type of Postural Deviation 71 Shoulder Abduction of Deviation 70 AB 3 Summit Training Source, Inc

42 ERGONOMIC JOB HAZARD ANALYSIS CHART Date Average daily hours performing task Completed by Number and duration of breaks (including lunch) Plant Daily units produced by operator Job Title/Desc. # of OSHA recordable injuries (past 12 months) # of employees doing this job ADDITIONAL RISK FACTORS 1. Is vibration a factor? 2. Is inadequate lighting/glare a factor? 3. Are there sharp edges on tables/machinery? 4. Is proper leg clearance impaired? 5. Does chair or table impinge thigh? 6. Do foot controls require excessive force? 7. Are elbows raised and unsupported? 8. Is excessive twisting of forearm/hand involved? Yes No TASK ELEMENTS GRIPS Pinch/Finger Hand/Power Low Force = 1 High Force = 1 High Force = 2 Only L R L R COLUMN TOTAL (a) (b) (c) (d) COLUMN ZONE TOTAL Flexion/ Extension WRIST BACK NECK SHOULDER Radial/Ulnar Deviation L R L R Flexion/ Extens Rotation Lateral Bend Flexion/ Extens Rotation Lateral Bend Flexion/ Extension Abduction/ Adduction L R L R (e) (f) (g) (h) (i) (j) (k) (l) (m) (n) (o) (p) (q) (r) WRIST BACK NECK SHOULDER s s s s Flex. Ext. Radial Ulnar Rot. Lat. Flex. Ext Rot. Lat. Flex. Ext Flex. Ext. Abduct Adduct LEFT GRIP INDEX (a) + (c) = RIGHT GRIP INDEX (b) + (d) = LEFT WRIST INDEX (e) + (g) = RIGHT WRIST INDEX (f) + (h) = BACK INDEX (i) + (l) + (k) = NECK INDEX (l) + (m) + (n) = LEFT SHOULDER INDEX (o) + (q) = RIGHT SHOULDER INDEX (p) + (r) = LEFT WRIST EXPOSURE (Left Grip Index + Left Wrist Index) x Daily Units = RIGHT WRIST EXPOSURE (Right Grip Index + Right Wrist Index) x Daily Units = Summit Training Source, Inc

43 Manual Material Handling Job Hazard Analysis Objective When a MMH JHA is Warranted Selecting Functions for the MMH JHA Using Videotape MMH Job Hazard Analysis Chart Administrative Detail Task Elements Analyzing the Data MMH JHA Chart Summit Training Source, Inc. 39

44 The objective of the Manual Material Handling Job Hazard Analysis (MMH JHA) is to identify ergonomic risk factors that cause MSDs and find solutions that eliminate employee exposure. An analysis may be warranted if the following occurs: Two or more injuries are recorded on the OSHA Injury and Illness Log for a particular function or department or, There are three or more YES answers on 25 percent or more of the Ergonomic Checklists, and 25 percent of the samples collected in the Body Discomfort Chart indicate a particular body part as a 3 or higher. Objective of the Manual Material Handling Job Hazard Analysis When an Analysis is Needed Selecting Functions for the MMH JHA Select a person who represents the work experience and performance of the group that performs the same function. Since the analysis is focused on manual material handling, try not to use a worker with poor body mechanics. Using Videotape The MMH JHA requires the recording of some measurements. It is recommended that you film the job performance and record the data from the videotape. If possible, the task should be filmed from the front, back, and both sides. The worker should be framed in the view finder to capture all motions. To provide a scale for measurement, place a vertical yardstick or other object with known measurements in the picture at all times. This allows you to easily compute all heights and distances. The MMH Job Hazard Analysis Chart The MMH Job Hazard Analysis Chart is divided into two sections. For your use and as a reference tool, the whole chart is located on page 46 of this manual. The first section includes administrative details such as location, department, date, number of employees doing this job, and more. Selecting the Job Function to Analyze Videotaping the Job Function for Analysis Administrative Information on the MMH JHA Company Location Department Task (brief description) MMH JOB HAZARD ANALYSIS WORKSHEET Date Completed by # of OSHA recordable injuries (past 12 months) # of employees doing this job Significant body motions? YES ( ) NO ( ) Job Title Number and duration of breaks (including lunch) Summit Training Source, Inc. 40

45 The second section identifies the task elements and records the data to be analyzed. There are sixteen rows beginning with Row A. Row A: Row A includes task components such as LIFT, LOWER, PUSH, PULL, and CARRY. Using the videotape, analyze the task elements performed by the employee. Indicate in row A whether the individual lifts, lowers, pushes, pulls, or carries. List each task component in a separate column. Row B: Row B identifies any significant body motions associated with the task component or the task itself. These include bending, twisting, and reaching. Row 1: Row 1 is the weight of the object. This is measured in pounds and noted in the columns marked CARRY and LIFT. Row 2: Row 2 is the frequency of the task. Enter the number of times the task component is performed per minute for lift and carry since the DO FOR column is marked PCL. Row 3: Row 3 is the hand height at the start of the task component. Enter the height of the hands above the floor at the start of each task component. This is why it is important to have a known measurement in the video frame to establish a scale unit of measurement on the video monitor. The measurement is entered in inches. Row 4: Row 4 is the hand distance away from the body at the start. This distance is calculated by drawing a vertical line to the floor from the center of the hands and measuring the distance from the vertical line to the center of the heels. This measurement is entered in inches for each task component. Row 5: Row 5 is the hand height at the end of the lift. This measurement is entered in inches for each lift component. Enter the height of the hands from the floor at the end of the lift or lowering. Summit Training Source, Inc. 41

46 Row 6: Row 6 is the hand distance away from the body at the end of the lift. This distance is calculated by drawing a vertical line to the floor from the center of the hands and measuring the distance from the vertical line to the center of the heels. This measurement is entered in inches for each task component. Row 7: Row 7 is the width of the object being lifted or lowered. This measurement can be obtained from the actual object and is entered in inches. Row 8: Row 8 is the back rotation angle. Enter the angle of rotation of the back during lifting and lowering. To measure back rotation, draw a vertical line between the center of both shoulders and a horizontal line through the center of the head. At the cross point of the two lines, draw a third line through the center of the shoulder with the most extreme position, either the left or right. Use a protractor to measure the angle and enter the degrees in the proper column. Row 9: Row 9 is task duration. Enter the number of hours the lifting and lowering task is performed. Row 10: Row 10 is the distance the object is pushed, pulled, or carried. The maximum distance that can be entered for calculation purposes is 200 ft. for pushing and pulling, and 28 ft. for carrying. The minimum distance is 1 ft. Row 11: Row 11 is initial force. Enter in pounds the amount of initial force required to push or pull an object. Initial force is measured by using a fish scale or similar device and recording the reading. Row 12: Row 12 is sustained force. Enter in pounds the amount of pushing or pulling force required to keep the object moving. This can be measured by using a fish scale or similar device. Row 13: Row 13 notes whether proper handles are provided for the lifting and lowering tasks. A YES or NO is entered in the proper columns. Row 14: Row 14 notes whether handles are used by whole hands during lifting and lowering tasks. A YES or NO is listed in the appropriate columns. Summit Training Source, Inc. 42