Videotape Guidelines and Analysis

Video Guidelines for Ergonomic Evaluations

Obtaining good video documentation for ergonomic evaluations can be difficult — as the tasks are often performed in inaccessible areas with poor lighting conditions and a lot of extraneous movement taking place. This guide presents suggestions for capturing effective video documentation of potential ergonomic hazards.

Preparation

Use the OSHA Form 200 logs and 101s (and after January 1, 2002 the OSHA Form 300 series), complaint information, and interviews to help prioritize areas for taping. It is desirable to have at least a two-person team when performing an evaluation. One person can operate the video camera while the other can record task and employee information.

The equipment needed for an ergonomic inspection will generally include:

• Video camera with extra tapes and charged batteries,

• Tape measure,

• Small notebook,

• Fanny pack,

• Small scale (Chattillon or fish scale that can measure pull forces),

• Bungee cord or small piece of rope, and

• Questionnaires for employee interviews concerning ergonomic factors.

Other useful items may include:

• Stop watch,

• Lens cleaning paper,

• Extra batteries for internal clock, and

• Skylight UV filter. This is a must in a dirty environment if you do not have a protective case.

The following are general suggestions on camera usage which, if reviewed prior to going on-site, will provide the best video documentation for the analyst and ensure that all pertinent information is obtained and documented.

• Become familiar with the camera and read the operators manual. Shoot some test footage so you are familiar with all the functions of the camera.

• Always activate the date and time mechanism on the camera so that this information is displayed on the video during the entire taping series. This will provide additional reference points with which to correlate written information with the videotape footage. Be aware of the position of the date and time printout on the video footage to make sure that it is not superimposed over the top of important features of the video documentation.

• For operations with extraneous movement it may be necessary to use the manual focus to avoid the camera refocusing on irrelevant moving objects. Determine where the focus point is for the camera you are using. It may not be in the center of the viewfinder. To make this determination place the camera on auto focus and try to focus on a small item such as a hanging pendant that has nothing else in the same plane. Hang the item from a doorway and try to focus by moving the item back and forth in the field of the viewfinder. You have found the focus point when the camera focuses on the item.

• If the camera has a high speed shutter, turn it off and use the auto shutter. high speed requires too much light for most industrial tasks. If you are taping a worker with dark clothes against a light background (such as a window, or a white wall), activate the "back lit" capability on the camera.

• Practice visual slating of information. This should be done by filming a piece of paper with information clearly written on it just prior to or directly after videotaping the task. Use a marker or dark pen that can be clearly seen. The macro-zoom on your camera will permit use of a small notebook or journal to be used as a slate. A small notebook is easy to carry and any pertinent notes can be recorded on the slate sheet for easy correlation and future reference. Macro-zoom is also helpful for documentation of small informational areas such as labels.

• If visual slating is absolutely not possible, cover the lens with your hand and record the information verbally before the actual job taping begins. Be aware that you will need to speak directly into the camera microphone to be clearly understood. Use of an external microphone can be helpful in audio slating.

• Hold the camera as still as possible or use a tripod if available. Don't walk with the camera unless absolutely necessary to record the task. When you change location, move slowly and minimize camera movement. Use the zoom instead of walking whenever possible. Use the manual focus whenever there is extraneous movement in the frame of action to ensure the focus will be on the items of interest.

Videotaping Tasks

The following items outline the procedures used for obtaining useful video documentation.

• If possible tape the operation in the order of production. Do the beginning of the production process first and proceed through all tasks of interest.

• Visually slate at least the name of the task just prior to or directly after videotaping the task.

• Tape 5–10 minutes for all jobs including approximately 10 cycles. A cycle is considered to be a set of repeated motions during which one part or assembly is processed. Jobs that have relatively long cycle times in excess of 30–60 seconds may require fewer than 10 cycles if all aspects of the job are recorded at least 3–4 times.

• Begin each task with a whole-body view of the worker from the side including the chair and/or the floor. Hold this view for 2–3 cycles and then zoom the camera in for a closer view of the area of principal interest. Tape from a variety of angles to allow a determination of wrist deviation, arm postures, back angles, etc. Tape from both sides and the front if possible. The total footage may be distributed between these different angles.

• Videotape the operation from a distance to give perspective to the analyst about workstation layout.

• Find an entity of known dimension in the frame of the picture and measure it for reference purposes. The employee's forearm from the wrist to the elbow is a convenient landmark since it is in most frames and is measurable on the television screen. If possible place a piece of contrasting tape on the reference points to provide a more distinct and identifiable location point. Record the reference dimensions either by visually slating the information or verbally recording the data. If using a ruler or tape measure as your reference point, ensure that the increments are clearly visible.

• Obtain video footage of tools or machinery that are used on the job. Videotape labels from hand tools, machinery, weight from boxes, etc.

Additionally, the following information should be visually slated at the beginning of each individual task or recorded in a written supplemental factors checklist.

• The name of the task and employee.

• Anthropometry (height) of the employee.

• Ambient conditions when working in extreme areas (freezers, furnaces, etc.).

• Clothing and PPE (materials, etc.).

• The period of time in which the task is performed including work-rest schedules.

• The nature of injuries as determined from the 200's, 101's, 300's, or interviews.

• Weight and dimension of loads lifted.

• Dimensions of the work items seen in the shot (i.e., pallets, tables, shelving units, etc.).

• Vertical distance between origin and destination of lift. Horizontal distance the load is held from the body at the beginning and end of the lift. These distances can be estimated directly from the video documentation if measuring will significantly interfere with the operation. To do this there must be a clear view of the entire body and the work space, preferably in profile. Provide dimensional information on as many work items seen in the footage as possible.

• Distance loads must be carried.

• Production data to aid in determining if the video segment is representative of normal activity.

• Conditions that might affect grip or traction (ie., sand on the floor, ice on boxes being lifted, etc.).

Components of the Equation | Ergonomics

Horizontal Values Range between 10 Inches and 25 Inches

If the horizontal distance is less than 10 inches (25 cm), then H is set at 10 inches (25 cm). Although objects can be carried or held closer than 10 inches from the ankles, most objects that are closer than this cannot be lifted without interference with the body. The maximum value of H is 25 inches (63 cm). Objects at a distance of more than 25 inches from the ankles normally cannot be lifted vertically without some loss of balance.

Vertical Values Range between 0 and 70 Inches

The vertical location is limited by the floor surface and the upper limit of vertical reach for lifting (i.e. 70 inches or 175 cm). The vertical location should be measured at the origin and the destination of the lift to determine the travel distance (D).

Distance Values Range between 10 Inches and 70 Inches

The variable D is assumed to be at least 10 inches (25 cm), and no greater than 70 inches (175 cm). If the vertical travel distance is less than 10 inches (25 cm), then D should be set at the minimum distance of 10 inches (25 cm).

Asymmetry Values

The angle A is limited to the range from 0° to 135°. If A > 135°, then AM is set equal to zero, which results in a RWL of zero, or no load.

Frequency Value Range

Lifting frequency (F) for repetitive lifting may range from 0.2 lifts/minute to a maximum frequency that is dependent on the vertical location of the object (V) and the duration of lifting. Lifting above the maximum frequency results in a RWL of 0.0, except for discontinuous lifting where the maximum frequency is 15 lifts/minute.

Classification of Gripping Method (Coupling)

The hand-to-object coupling or gripping method (C) affects not only the maximum force a worker can or must exert on the object, but also the vertical location of the hands during the lift. A good coupling will reduce the maximum grasp forces required and increase the acceptable weight for lifting, while a poor coupling will generally require higher maximum grasp forces and decrease the acceptable weight for lifting. The entire range of the lift should be considered when classifying hand-to-object couplings, with classification based on overall effectiveness. The coupling must be classified as good, fair, or poor. If there is any doubt about a particular classification, select the more stressful classification.

Lifting Index (LI)

The Lifting Index (LI) provides a relative estimate of the physical stress associated with a manual lifting job. The equation for the (LI) is:

How to Use the RWL and LI to Guide Ergonomic Design

The recommended weight limit (RWL) and lifting index (LI) can be used to guide ergonomic design in several ways:

• The individual multipliers can be used to identify specific job-related problems. The relative magnitude of each multiplier indicates the relative contribution of each task factor (e.g., horizontal, vertical, frequency, etc.).

• The RWL can be used to guide the redesign of existing manual lifting jobs or to design new manual lifting jobs. For example, if the task variables are fixed, then the maximum weight of the load could be selected so as not to exceed the RWL; if the weight is fixed, then the task variables could be optimized so as not to exceed the RWL.

• The LI can be used to estimate the relative magnitude of physical stress for a task or job. The greater the LI, the smaller the fraction of workers capable of safely sustaining the level of activity. Thus, two or more job designs could be compared.

• The LI can be used to prioritize ergonomic redesign. For example, a series of suspected hazardous jobs could be ranked according to the LI and a control strategy could be developed according to the rank ordering (i.e., jobs with lifting indices above 1.0 or higher would benefit the most from redesign).

This Lifting Index can be used to identify potentially hazardous lifting jobs or to compare the relative severity of two jobs for the purpose of evaluating and redesigning them. Lifting tasks with a LI > 1.0 pose an increased risk for lifting-related low back pain for a fraction of the workforce. Therefore, the goal should be to design all lifting jobs to achieve a LI of 1.0 or less.

Training and Education | Ergonomics

One of the purposes of training and education is to ensure that employees are sufficiently informed about the ergonomic hazards to which they may be exposed so they are better able to participate actively in their own protection. Suggestions and input from workers who are educated about ergonomic hazards can be very helpful in designing improved work practices to reduce ergonomic hazards.

A good ergonomics education and training program will teach employees how to properly use equipment, tools, and machine controls, as well as the correct way to do a variety of job tasks. For example, to minimize or prevent back disorders, workers can be taught proper postures and lifting techniques. Using correct posture is important whether an employee is sitting, standing, pulling, pushing, lifting, or using tools or equipment or whether the job is in a factory setting or an office setting.

Provide MSD Information

Employees need access to MSD information in order to be alert to the onset of signs or symptoms and to effectively participate in the ergonomics program, as well as to protect themselves while at work. You should provide the information periodically, that is on a regular basis appropriate for the conditions in the workplace.

That means as often as needed, such as when significant changes are made in the workplace that may result in increased exposure to MSD hazards. Examples of significant changes in the workplace include the introduction of new equipment, new processes, or new production demands that may increase the likelihood that employees will be exposed to MSD hazards.

The information provided to current and new employees (either written or oral) should include:

• Common MSD hazards;

• The signs and symptoms of MSDs and the importance of reporting them early; and

• How to report MSD signs and symptoms.

Presentation Methods

There are many practical ways to present the information. One method that aids the understanding of technical information is to allow employees an opportunity to ask questions and receive answers. Examples include question and answer sessions that are:

• Organized classroom style;

• Part of regularly scheduled meetings with employees and their supervisors;

• An outgrowth of informal talks with employees; and

• Incorporated into safety meetings.

Merely arranging for employees to view a videotape on common MSD hazards, without an opportunity for discussion or questions and answers, won't ensure that the information has been effectively communicated. Provide the information in the language and at levels that employees comprehend.

While training and education are an important part of an ergonomic hazard prevention program, they should not be considered the sole solution to the problem. Training in good lifting techniques, for example, is only likely to change existing employee habits for a short period of time. After that, people begin to forget and old habits return. Regular retraining is necessary in order to refresh memories.

Also, training will have a limited impact on an employee whose job still requires a great deal of repetitive motion, twisting, or heavy lifting. In these instances, the problem lies not with the person performing the job, but with the job itself. Other prevention strategies will need to be used in addition to training in order to improve the job such as tool or workstation redesign.

Medical Management | Ergonomics

In general, health care management emphasizes the prevention of impairment and disability through early detection, prompt treatment, and timely recovery. Medical management responsibilities fall on employers, employees, and health care professionals (HCPs). A medical management program can help to either eliminate or substantially reduce the risk of development of ergonomics-related problems and symptoms through early identification and treatment.

Identifying and addressing signs and symptoms at an early stage helps to slow or halt the progression of the disorder. When MSDs are caught early, they are more likely to be reversible, to resolve quickly, and not to result in disability or permanent damage. Early intervention plays a big part in reducing the need for surgery.

Employer Responsibilities

An employer's basic obligation is to make MSD management available promptly to employees with work-related MSDs. In other words, MSD management means that you have established a process for assuring that employees receive timely attention for it, including, if appropriate, work restrictions or job accommodation and follow-up.

Where there is no onsite HCP, an individual should be designated to receive and respond promptly to reports of MSD signs, symptoms, and hazards. Where there is an onsite HCP, he or she would be the likely person to have responsibility for MSD management, including referral as appropriate.

An effective MSD management program has:

1. A method for identifying available appropriate work restrictions and promptly providing them when necessary;

2. A method for ensuring that an injured employee has received appropriate evaluation, management, and follow-up in the workplace;

3. A process for input from persons contributing to the successful resolution of an employee's covered MSD; and

4. A method for providing relevant information and communicating with the safety and health professionals and HCPs involved in the process.

Employee Responsibilities

Employees should participate in the health care management process by:

• Following applicable workplace safety and health rules,

• Following work practice procedures related to their jobs, and

• Reporting early signs and symptoms of MSDs.

Employees may be faced with conflicting job demands or requirements. Safe work practices or rules may conflict with pressures or incentives to be more productive.

Health Care Professional Responsibilities

Health care professionals who evaluate employees, determine employees' functional capabilities, and prepare opinions regarding work relatedness should be familiar with employee jobs and job tasks. With specific knowledge of the physical demands involved in various jobs and the physical capabilities or limitations of employees, the HCP can match the employees' capabilities with appropriate jobs. Being familiar with employee jobs not only assists the HCP in making informed case management decisions but also assists with the identification of ergonomic hazards and alternative job tasks.

The health care professional should:

• Acquire experience and training in the evaluation and treatment of MSDs.

• Seek information and review materials regarding employee job activities.

• Ensure employee privacy and confidentiality to the fullest extent permitted by law.

• Evaluate symptomatic employees including:

  • Medical histories with a complete description of symptoms,

  • Descriptions of work activities as reported by the employees,

  • Physical examinations appropriate to the presenting symptoms and histories,

  • Initial assessments or diagnoses,

  • Opinions as to whether occupational risk factors caused, contributed to, or exacerbated the conditions, and

  • Examinations to follow-up symptomatic employees and document symptom improvements or resolutions.

Engineering Controls | Ergonomics

The preferred means of controlling or reducing ergonomic hazards in the workplace is through the use of engineering controls. After all, the primary focus of ergonomic hazard abatement is to make the job fit the person, not force the person to fit the job. These are typically permanent controls and can be accomplished by ergonomically designing workstations, tools, or equipment.

The preferred approach to prevent and control musculoskeletal disorders is to design the job — including (1) the workstation layout, (2) selection and use of tools, and (3) work methods — to take account of the capabilities and limitations of the workforce. Engineering control strategies to reduce ergonomic risk factors include the following:

• Changing the way materials, parts, and products can be transported.

• Changing the process or product to reduce worker exposures to risk factors.

• Modifying containers and parts presentation, such as height-adjustable material bins.

• Changing workstation layout, which might include using height-adjustable workbenches.

• Changing the way parts, tools, and materials are to be manipulated. Examples include using fixtures (clamps, vice-grips, etc.) to hold work pieces to relieve the need for awkward hand and arm positions or suspending tools to reduce weight and allow easier access.

• Changing tool designs — for example, squeeze-grip-actuated screwdrivers to replace finger-trigger-actuated screwdrivers.

• Changes in materials and fasteners such as lighter weight packaging materials to reduce lifting loads.

Control the Hazards | Ergonomics

Risk factors can be controlled either during the development stages of a product or process or after work has begun. In the development stages, very effective controls can be achieved (proactively) for a small investment. Once production has begun, changes can still be implemented (retrofit changes) but usually require modifications to existing equipment. Retrofit changes also require workers to change work patterns. Implementing a change after habits have been formed requires that the need, the objective, the time frame, and the consequences of the change be communicated. One way to ensure this communication is through employee involvement.

After risk factors and their causes have been identified, either in development or after implementation, the next step is to identify control measures that reduce or eliminate the presence of these factors. Traditional classification of control measures distinguishes between engineering controls and administrative controls. Opportunities for both types of controls differ depending on whether the job or process is new or existing.

A three-tier hierarchy of controls is widely accepted as an intervention strategy for controlling workplace hazards, including ergonomic hazards. These procedures should be evaluated when determining how to correct or control your ergonomic hazards:

• Engineering controls to reduce or eliminate potentially hazardous conditions (e.g., work station, tool, and equipment design or redesign).

• Administrative controls, usually changes in work practices and management policies (e.g., worker rotation, reduced production demand, and increased rest breaks).

• Personal protective equipment

Worksite Analysis | Ergonomics

A worksite analysis provides for both the identification of problem jobs and risk factors associated with these jobs. The worksite analysis can be used to determine what jobs and workstations are the source of the greatest problems. Recognizing the signs that may indicate a problem through a systematic analysis of injury and illness records can be done to accomplish this step.

Analyze Company Data

First, analyze all existing medical, safety, and insurance records, including the OSHA 200 log and workers' compensation claims for evidence of ergonomic illnesses such as carpal tunnel syndrome, tendonitis, tenosynovitis, and low back pain. When you analyze the OSHA 200 log, look for these clues relating to cumulative trauma disorders associated with ergonomically hazardous jobs.

• When the illness began (was there a lot of overtime, a speed-up in production, or introduction of new equipment around this time).

• What is the employee's job title and department (a clue to the type of tasks being performed).

• Column F: Description of injury or illness. Terminology given may be confusing. Some key terms for cumulative trauma disorders include arthritis, carpal tunnel, numbness, pain, strain, and tendonitis. Check your first report of injury forms for more details on questionable cases.

• Column 7f: Disorders associated with repeated trauma. Check thoroughly. Not all repeated trauma cases are posted in this column. The descriptions in Column F are more inclusive, so always check both columns.

• Back disorders are not listed in Column 7f. Even though they are usually due to repeated trauma, they are classified as injuries on the 200 form and must be listed in Column F. You need to check there for back-related CTDs.

This process may need to involve health care providers to ensure confidentiality of patient records.

Identify and Analyze Trends

Second, identify and analyze any apparent trends or ergonomic problems relating to particular departments, process units, production lines, job titles, operations, or workstations.

• Certain jobs or work conditions cause worker complaints of undue strain, localized fatigue, discomfort, or pain that does not go away after overnight rest.

• Workers visiting the clinic make frequent references to physical aches and pains related to certain types of work assignments.

• Job tasks involve activities such as repetitive overhead lifts; awkward work positions; or use of vibrating equipment.

A company's initial efforts in ergonomics should be directed toward fixing the most obvious problem jobs. Implementing the program can have value by enabling early detection of and more timely interventions in potential ergonomic problems. Also, an ergonomics program can influence the design of future changes in work processes to reduce the possibility of musculoskeletal disorders.

This information will provide you with an idea about where "problem jobs" exist. Worker surveys and a background knowledge of certain jobs considered "high risk" can also help in targeting specific worksite analyses. Employee questionnaires on ergonomic problems and issues are a useful way to gather information about work conditions that may contribute to ergonomic hazards. Other forms of regular employee participation might include a complaint log or a suggestion book.

Determine Risk Factors

The next step to take is conducting a more detailed analysis of those job tasks and positions determined to be problem areas for their own specific ergonomic risk factors. This analysis can be done with a checklist and should be performed either by direct observation or, where feasible, through videotape review. The analysis should be routinely performed and documented by a qualified person, ideally an ergonomist, although trained engineers, managers, health care providers, and affected employees can often contribute significantly to the process.

A combination of risk factors rather than any single factor may be responsible for the occurrence of musculoskeletal disorders. Therefore, identifying all the risk factors that may be present in the job is important. Some typical risk factors for cumulative trauma and back disorders that are likely to be identified in a worksite analysis include:

• Excessive repetition or prolonged activities such as for an 8-hour shift, cause fatigue and muscle/tendon strain which can accumulate and may result in permanent tissue damage.

• Forceful exertions (including lifting, pushing, and pulling) place higher loads on the muscles, tendons, and joints. As the force increases, the muscles fatigue more quickly.

• Pinch grips which usually place three to four times more force on the tendons than power grips.

Postures determine which muscles are used in an activity and how forces are translated from the muscles to the object being handled. More muscular force is required when awkward postures are used because muscles cannot perform efficiently.

Look for these postures when analyzing a task:

• Prolonged static postures of the body, trunk or its extremities, either sitting or standing.

• Awkward postures of the upper body, including reaching above the shoulders or behind the back.

• Excessive bending or twisting of the hand or wrist.

• Continued elevation of the elbow and forearm.

• Continued physical contact with work surfaces, such as contact with edges of machines can inhibit nerve function and blood flow.

• Inappropriate or inadequate hand tools that cause awkward posturing.

• Restrictive workstations and inadequate clearances that may cause stooping and bending.

• Improper seating or support.

• Bad body mechanics such as continued bending at the waist, continued lifting below the knuckles or above the shoulders, or twisting at the waist while lifting.

• Lifting heavy objects or objects of abnormal sizes without mechanical aids.

• Lack of adjustable chairs, footrests, body supports, and work surfaces at workstations or slippery footing.

Perform the Job Analysis

Job analysis breaks a job into its various elements or actions, describes them, measures and quantifies risk factors inherent in the elements, and identifies conditions contributing to the risk factors. Most job analyses have several common steps. Each task is studied to determine the specific risk factors that occur during the task. Sometimes each risk factor is evaluated in terms of its magnitude, that is, the number of times it occurs during the task, and how long the risk factor lasts each time it occurs.

The tasks of most jobs can be described in terms of (1) the tools, equipment, and materials used to perform the job, (2) the workstation layout and physical environment, and (3) the task demands and organizational climate in which the work is performed. Job screening provides some of this data. More definitive procedures for collecting information on these components can include the following:

• Observing the workers performing the task in order to furnish time-activity analysis and job or task cycle data; videotaping the workers is typically done for this purpose.

• Still photos of work postures, workstation layouts, tools, etc., to illustrate the job.

• Workstation measurements (e.g., work surface heights, reach distances).

• Measuring tool handle sizes, weighing tools and parts, and measuring tool vibration and part dimensions.

• Determining characteristics of work surfaces such as slip resistance, hardness, and surface edges.

• Measuring exposures to heat, cold, and whole body vibration.

• Biomechanical calculations (e.g., muscle force required to accomplish a task or the pressure put on a spinal disc based on the weight of a load lifted, pulled or pushed).

• Physiological measures (e.g., oxygen consumption, heart rate).

• Special questionnaires, interviews, and subjective rating procedures to determine the amount of perceived exertion and the psychological factors influencing work performance.

Jobs in which current cases have been identified should receive immediate attention, followed by those in which past records have noted a high incidence or severity of musculoskeletal disorders despite the lack of current cases. Priority for job analysis and intervention should be given to those jobs in which most people are affected or in which work method changes are going to be taking place anyway.

The analysis should take multiple causes into consideration, as the combined effect of several risk factors often results in the onset of cumulative trauma disorders. Jobs, operations, or workstations that have multiple risk factors have a higher probability of causing these disorders.

Ideally, all risk factors within a problem area should be identified and proper controls implemented to eliminate each of them. The goal of an ergonomic approach is to make things better than they were before. Incremental improvements in reducing or eliminating some, if not all, risk factors within a problem area will reduce the cumulative risk and the overall level of physical stress for the worker. Thus, the benefits of hazard prevention and control strategies can be quite significant.

Tackling Ergonomic Hazards | Ergonomics

The first step in setting up an ergonomics program is to determine if musculoskeletal disorders are present. Recognizing the signs that a problem exists is the first step. Some signs are obvious while others are more subtle. Look for signs such as the following:

• OSHA Form 200 logs or workers' compensation claims show cases of MSDs such as carpal tunnel syndrome, tendinitis, tenosynovitis, epicondylitis, and low back pain. Sometimes these records contain nonspecific entries like "hand pain," which, while not a specific diagnosis, may be an indicator of a significant health problem if severe or persistent.

• Certain jobs or work conditions cause worker complaints of undue strain, localized fatigue, discomfort, or pain that does not go away after overnight rest.

• Workers visiting the clinic make frequent references to physical aches and pains related to certain types of work assignments.

• Job tasks involve activities such as repetitive and forceful exertions; frequent, heavy, or overhead lifts; awkward work positions; or use of vibrating equipment.

Other signals that alert employers to potential problems include the following:

• Trade publications, employers' insurance communications, and references in popular literature indicating risks of MSDs connected with job operations in the employer's business.

• Cases of MSDs found among competitors or in similar businesses.

• Proposals for increasing line speed, retooling, or modifying jobs to increase individual worker output and overall productivity.

Clues that indicate ergonomic problems may also suggest the scope of the effort required to correct them. Signs that implicate multiple jobs in various departments and involve a large percent of the workforce may indicate the need for a full-scale, company-wide program. Signs that the suspected problems are confined to isolated tasks and relatively few workers may suggest starting with a more limited, job-focused activity.

The financial benefits of comprehensive safety and health programs have been well documented. Workplaces safe from hazardous conditions have lower costs due to decreased lost time, absenteeism, and worker compensation premiums. Ergonomics programs have been shown to be cost effective for similar reasons. In addition, ergonomic improvements may result in increased productivity and higher product quality.

Risk Factors that Cause MSDs | Ergonomics

The physical stresses that can contribute to or cause MSDs are called "risk factors." The initial symptoms of MSDs may include fatigue, discomfort, and pain; as tissue damage worsens, other symptoms, such as weakness, numbness, or restricted movement, may also appear. Work-related MSDs occur when the risk factors that cause or contribute to musculoskeletal system pathology are associated with a person's job duties. Workplace musculoskeletal disorders are caused by exposure to the following risk factors:

Repetition

Doing the same motions over and over again places stress on the muscles and tendons. The severity of risk depends on how often the action is repeated, the speed of movement, the number of muscles involved, and the required force.

Forceful Exertions

Force is the amount of physical effort required to perform a task, such as heavy lifting or pushing/pulling, or to maintain control of equipment or tools. The amount of force depends on the type of grip, the weight of an object, body posture, the type of activity, and the duration of the task.

Awkward Postures

Posture is the position your body is in and affects muscle groups that are involved in physical activity. Awkward postures include repeated or prolonged reaching, twisting, bending, kneeling, squatting, working overhead with your hands or arms, or holding fixed positions.

Contact Stress

Pressing the body against a hard or sharp edge can result in placing too much pressure on nerves, tendons, and blood vessels. For example, using the palm of your hand as a hammer can increase your risk of suffering an MSD.

Vibration

Operating vibrating tools or equipment that typically have high or moderate vibration levels such as sanders, grinders, chippers, routers, drills, and other saws can lead to nerve damage.

Don't Wait to Start an Ergonomics Program

Data shows that employers with effective, well-managed ergonomics programs see significant reductions in the severity and number of work-related MSDs. These programs also generally improve productivity and employee morale and reduce turnover and absenteeism.

Even though OSHA's ergonomics standard has been rescinded, your workers' safety and health and rising workers' compensation claims are reason enough for you to carefully analyze your company's work environment, the equipment used, and the tasks performed from an ergonomics perspective. If you do not feel competent to make the evaluation, bring in outside assistance. There are various government and private agencies that are capable of doing a workplace analysis.

Common MSDs | Ergonomics

The most common MSDs in the workplace are tendon disorders such as tendinitis, tenosynovitis, De Quervain’s disease, trigger finger, Raynaud’s syndrome, and carpal tunnel syndrome. Tendon disorders often occur at or near the joints where the tendons rub against ligaments and bones. The most frequently noted symptoms of tendon disorders are a dull aching sensation over the tendon, discomfort with specific movements, and tenderness to the touch. Recovery is usually slow and the condition may easily become chronic if the cause is not eliminated.

Tendinitis

Tendinitis is tendon inflammation that occurs when a muscle or tendon is repeatedly tensed from overuse, vibration, or unaccustomed usage of the wrist and shoulder. With further exertion, some of the fibers that make up the tendon can actually fray or tear apart. The tendon becomes thickened, bumpy, and irregular in certain areas of the body, such as the shoulder, and the injured area may calcify. Without rest and sufficient time for the tissues to heal, the tendon may be permanently weakened. Tendinitis is common among power press operators, welders, painters, and assembly line workers in the automobile, appliance, and electronic production industries.

Tenosynovitis

Tenosynovitis is an inflammation or injury to the synovial sheath surrounding the tendon. These sheaths secrete synovial fluid which acts as a lubricant to reduce friction during movement. Repetitive motion using the hands and wrists may provoke an excessive secretion of synovial fluid, with the sheath becoming swollen and painful. Repetitions exceeding 1,500 to 2,000 per hour are known to produce symptoms associated with tendon sheath irritation in the hands. Tenosynovitis often affects workers in meatpacking and poultry processing. Also those whose tasks require buffing, grinding, sanding, sawing, and punch press operations.

DeQuervain's Disease

In DeQuervain’s disease, the tendon sheath of the thumb is inflamed. This disease is attributed to excessive friction between two thumb tendons and their common sheath. Twisting and forceful gripping motions with the hands, similar to a clothes-wringing movement, can place sufficient stress on the tendons to cause DeQuervain’s disease. Tasks involving these kinds of motions are frequently performed by butchers, housekeepers, packers, seamstresses, and cutters.

Trigger Finger

Trigger finger, another tendon disorder, is attributed to the creation of a groove in the flexing tendon of the finger. If the tendon becomes locked in the sheath, attempts to move that finger will cause snapping and jerking movements. The palm side of the fingers is the usual site for trigger finger. This disorder is often associated with using tools that have handles with hard or sharp edges or whose handles are too far apart for the user’s hand. Meatpackers, poultry workers, electronic assemblers, and carpenters are at risk of developing trigger finger.

Carpal Tunnel Syndrome

Carpal tunnel syndrome (CTS), a disorder affecting the hands and wrists, has probably received more attention in recent years than any other musculoskeletal disorder. CTS is the compression and entrapment of the median nerve where it passes through the wrist into the hand in the carpal tunnel. The median nerve is the main nerve that extends down the arm to the hand and provides the sense of touch in the thumb, index finger, middle finger, and half of the fourth or ring finger.

When irritated, tendons housed inside the narrow carpal tunnel swell and press against the nearby median nerve. The pressure causes tingling, numbness, or severe pain in the wrist and hand. The pain is often experienced at night. The pressure also results in a lack of strength in the hand and an inability to make a fist, hold objects, or perform other manual tasks. If the pressure continues, it can damage the nerve, causing permanent loss of sensation and even partial paralysis.

Carpal tunnel syndrome develops in the hands and wrists when repetitive or forceful manual tasks are performed over a period of time. Workers need to be aware of the symptoms and causes of CTS and what to do about them. Initially, they may have fatigue and pain which develops during the work day and disappears overnight with no physical symptoms. After a length of time, fatigue and pain develop earlier in the day, some physical symptoms such as clumsiness may occur which affect work performance, and there may be no overnight recovery.

When the case becomes full-blown, there is constant fatigue and pain with no overnight recovery and disturbed sleep results. At this point, work performance is inhibited to the extent of requiring off-duty time or light/restricted duty. Often workers do not associate their pain with their work because symptoms may only occur during evening or off-duty hours. When they finally seek medical help, surgery may be necessary and the road to recovery will take more time than anticipated.

Raynaud's Syndrome

Raynaud’s syndrome, or white finger, occurs when the blood vessels of the hand are damaged as a result of repeated exposure to vibration for long periods of time. The skin and muscles are unable to get the necessary oxygen from the blood and eventually die. Common symptoms include:

• Intermittent numbness and tingling in the fingers;

• Skin that turns pale, ashen and cold; and

• Eventual loss of sensation and control in the fingers and hands.

Raynaud’s syndrome is associated with the use of vibrating tools over time, such as pneumatic hammers, electric chain saws, and gasoline powered tools. After long-term exposure, the blood vessels in the fingers may become permanently damaged. This condition is also intensified when the hands are exposed to extremely cold temperatures.

There is no medical remedy for white finger. If the fingers are fairly healthy, the condition may improve if exposure to vibration stops or is reduced. Job activities that can lead to Raynaud’s Syndrome include chain sawing, jack hammering, use of vibrating tools, sanding, painting, and using a tool too small for the hand, often in a cold environment.

Other types of vibration may affect the entire body, producing overall fatigue and potential permanent damage. Vibration in conjunction with prolonged sitting may also result in degenerative changes in the spine. For example, drivers of tractors, trucks, buses, construction machinery, and other heavy equipment may suffer from low back pain, and permanent abdominal, spinal and bone damage.

Back Disorders

Pulled or strained muscles, ligaments, tendons, and disks are perhaps the most common back problems and may occur in almost half of the work force at least once during their lifetime. The majority of workplace back disorders result from chronic, or long-term injury to the back rather than from one specific incident. Only about four percent of back injuries are associated with a single traumatic incident.

Back disorders are frequently caused by the cumulative effects of faulty body mechanics:

• Excessive or repetitive twisting, bending, and reaching;

• Carrying, moving, or lifting loads that are too heavy or too large;

• Staying in one position for too long;

• Poor physical condition; or

• Awkward posture.

When back muscles or ligaments are injured from these repetitive pulling and straining activities, the back muscles, disks, and ligaments can become scarred and weakened and lose their ability to support the back, making additional injuries more likely.

Prolonged sitting stresses the body, particularly the lower back and the thighs, and may cause the lower back (lumbar) region to bow outward if there is inadequate support. This abnormal curvature (called kyphosis) can lead to painful lower back problems, a common complaint among office workers.

Other factors which are contributors to back injuries include the natural degeneration of the back due to aging, inactivity both at work and at home, seasonal activity undertaken without prior physical conditioning, stress, and vibration.

State-Plan States Move Forward with Ergonomics Rules

California—Title 8, Section 5110, Ergonomics Rule

The State of California Department of Industrial Relations began to develop the nation’s first rule addressing repetitive motion injuries in the mid-1990s. The rulemaking was mandated by a provision in a workers’ compensation bill passed by the California Legislature in 1993 which required that the Cal/OSHA Standards Board promulgate an ergonomics standard designed to prevent injuries caused by repetitive motion. In November 1996, Section 5110, Repetitive Motion Injuries, a new section to the California Title 8, General Industry Safety Orders was adopted.

The standard applies repetitive motion injuries that are work-related (50 percent or more of the worker’s job) which have been identified and diagnosed by a licensed physician. Covered employers must establish and implement a program that includes a worksite evaluation, control of exposures which have caused repetitive motion injuries, and training for employees. Employers with nine or fewer employees are exempted. Since the rule became effective on July 3, 1997, Cal/OSHA has issued several citations under it.

Washington—Part 296-62-05101

Following California’s lead, in May 2000, the state of Washington became the country’s second state to adopt its own ergonomics rule. To ensure that the rule will work correctly before any enforcement occurs, the Department of Labor and Industries (LandI) implemented voluntary demonstration projects prior to enforcement.

The ergonomics rule requires employers to evaluate jobs to identify potential ergonomic risks such as awkward posture, frequent or heavy lifting, hand-arm vibration, force, or highly repetitive motion. Employers will have to reduce employee exposure when it is determined that jobs meet these risk factors and provide basic ergonomics education for employees who work in or supervise high risk jobs.

Revised: 2002/10
The rule is being phased in over a five year period, beginning in July 2002. Implementation dates range from July 1, 2002 through July 1, 2006, but enforcement will be delayed until July 2004. The two-year enforcement delay means that LandI will impose no penalties under the rule for two years after each effective date on the timeline.

Alaska

Revised: 2002/10

Alaska’s Department of Labor and Workforce Development has held state-wide meetings to get public input on developing regulations for several safety and health issues, including ergonomics. The Department will evaluate and incorporate public input from these meetings into draft regulations, and propose in a formal rulemaking process.

Minnesota

Revised: 2002/10

In February 2002, Minnesota legislators introduced bills that would require the state’s commissioner of labor and industry to adopt a standard regulating workplace ergonomic hazards. The bills mandate rules addressing ergonomic risk factors for awkward postures; force; repetitive motions; repeated impacts; heavy, frequent, or awkward lifting; and vibration. They would cover all industries where workers are exposed to workplace ergonomic hazards and where there are economically and technologically feasible measures to control these hazards. In June, the Minnesota Department of Labor and Industry established a task force to review the state’s current approach to ergonomic issues and make recommendations for future actions.

NIOSH Develops Guide for Ergonomics Program Development

In 1997, the National Institute for Occupational Safety and Health (NIOSH) issued guidelines for developing practical and cost-effective approaches to protecting workers from job-related musculoskeletal disorders. It describes the basic elements of a workplace program aimed at preventing work-related MSDs by focusing on management commitment, worker participation, and training as essential elements in an overall ergonomics program. It also includes a "toolbox" which is a collection of techniques, methods, reference materials, and other resource information to help employers develop a successful program.

Elements of Ergonomics Programs: A Primer Based on Workplace Evaluations of Musculoskeletal Disorders outlines methods that are commonly used for identifying, correcting, and preventing MSDs. The book, a culmination of two decades of NIOSH research, contains many illustrations and charts on how those techniques can be tailored for specific types of workplaces. It covers these basic steps for controlling work-related musculoskeletal disorders:

• Determine if musculoskeletal problems exist.

• Develop roles for both managers and workers in the ergonomics program.

• Recognize and fill training needs.

• Gather and analyze data to define the scope and characteristics of ergonomics concerns.

• Develop control solutions.

• Establish health care management.

• Create a proactive ergonomics program.

What is Ergonomics?

Ergonomics is the science of fitting the job to the worker. In the workplace, ergonomic principles are used to make alterations to a job so that it conforms to the person doing that job, rather than to force the person to fit the job. Redesigning various job functions to match a person's stature will reduce stress on the body and eliminate many potential injuries associated with the overuse of muscles, unnatural postures, and repetitive motions.

Ergonomic solutions may involve the redesign of tasks, workstations, tools, lighting, and equipment to fit a worker's physical capabilities and limitations. This may mean adjusting the height of a workstation or a computer screen, or rearranging the steps in a process so the worker will not have to lift and twist in the same motion.

Today, technological advances which result in more specialized tasks, higher assembly line speeds, and increased repetition are often major causes of ergonomic problems. Consequently, workers' hands, wrists, arms, shoulders, backs, and legs may be subjected to thousands of repetitive twisting, forceful, or flexing motions during a typical workday. When this occurs on the job, the stress on those body parts builds up over time and results in musculoskeletal disorders (MSDs).

The goal of a workplace ergonomics program is to reduce or eliminate the risk factors that lead to MSDs. Jobs that expose workers to excessive vibration, repetitive motions, heavy lifting, awkward postures, and continual contact pressure will be assessed and ways found to reduce exposure to those factors that cause MSDs. Identifying ergonomic risk factors in your workplace is the first step toward making changes that will improve the safety and health of all workers.

Bureau of Labor Statistics Reports on Ergonomic Injuries

In their 1998 report on lost-worktime injury and illness characteristics, the Bureau of Labor Statistics (BLS) reported that workers afflicted with carpal tunnel syndrome missed an average of 24 days of work. Women suffer from carpal tunnel syndrome more often than men. Surprisingly, more women sustained carpal tunnel syndrome by operating machinery, on assembly lines, and tending retail stores than they did typing, keying, and performing other duties associated with office workers.

Virtually all cases of carpal tunnel syndrome resulted from stress or strain on a worker's wrist due to a task's repetitive nature. Examples include grasping and unravelling bolts of cloth, scanning groceries, typing or data entry, and cutting meat or poultry on an assembly line. According to the BLS, these repetitive motion injuries resulted in the longest absences from work — an average of 15 days.

In 1998, there were nearly 593,000 musculoskeletal disorders reported, accounting for more than one out of three of the injuries and illnesses involving recuperation away from work. Manufacturing and services industries each accounted for 26 percent of the MSDs, followed by retail trade with 15 percent. Three occupations — nursing aides, orderlies, and attendants; truck drivers; and laborers, non-construction — together accounted for one out of five MSDs.

As the work force continues to age and medical costs continue to escalate, the cost of ergonomic-related illnesses in the workplace will rise. If you look beyond worker health and the dollars-and-cents side of the issue, however, there is at least one other reason why you should be concerned with ergonomic hazards in the workplace. Even though OSHA's ergonomics standard has been withdrawn, the Agency can and will continue to cite and fine companies with a pattern of ergonomic-related injuries under the 5(a)(1) or General Duty clause of the OSH Act.

Why is Ergonomics a Concern?

In the past, workers were usually trained to perform the task and any changes made to work processes were done for reasons relating to productivity, without regard to worker comfort. For example, incorporating the assembly line into production facilities increased production rates, but necessitated that each worker in the line perform the same task or tasks all day long, often at increasing production rates. These same changes in production methods, which were often made as a result of technological advances that saved companies hundreds or thousands of dollars, are now costing companies in the form of workers' compensation claims, lost work time, and training.

Many of these technological advances require workers to perform repetitive procedures or work in positions that put a great deal of stress on the musculoskeletal system. This stress can be caused by any number of factors including repetitive motion, excessive force, mechanical stresses caused by tools or machines, poor posture, awkward positioning, lifting, vibrations, temperature extremes, and unaccustomed activity.

The cost of worker injuries and illnesses caused by these ergonomic stressors is staggering. Over one third of all workers' compensation costs are associated with musculoskeletal disorders (MSDs), injuries caused by trauma to the body occurring over a period of time. A conservative estimate of the medical costs of treating one industrial case of carpal tunnel syndrome, a type of disorder affecting the wrists and hands, is about $20,000 a year.

This cost estimate does not take into consideration the costs involved with lost work time, replacement workers, and reduced productivity. Lower back pain, for example, which is often associated with improper or repeated lifting or sitting for an extended period of time, is responsible for about 1,400 lost work days per 1,000 workers every year. Only the common cold and the flu cause workers to miss more work annually.