Acute back disorders, on the other hand, can be the immediate result of improper lifting techniques and/or lifting loads that are too heavy for the back to support. While an acute disorder may seem to be caused by a single well-defined incident, the real cause is often a combined interaction of the observed stressor coupled with years of weakening of the musculoskeletal support mechanism by repetitive micro-trauma. These disorders can arise in muscle, ligaments, vertebrae, and discs, either singly or in combination.
Whether chronic or acute, back disorders have the following signs and symptoms:
- Pain when attempting to assume normal posture,
- Decreased mobility, and
- Pain when standing or rising from a seated position.
Editor’s Note: Sources of the In Depth section are listed in the Acknowledgements section.
Did You Know
Of all the parts of the body affected by injuries and illnesses involving days away from work (DAFW), the back dominates the list, with about 4,420 cases per year in the warehousing and storage industry. That’s 20.7 percent of all DAFW cases affecting the industry annually. In comparison, employees in the industry suffer 2,385 shoulder-related cases and 1,840 hand-related cases each year. Source: Bureau of Labor Statistics 2017 to 2020 average.
Risk Factors
The spinal cord consists of 24 vertebrae, each separated from the next by soft discs that act as shock absorbers when the vertebra move. Abdominal muscles, as well as other muscles and ligaments that run along the spinal column, support the spine. However, if an employee’s spine is not properly supported by these muscles, a quick twist or off-balanced lift, for example, can easily result in a low-back injury. Because the lower back (the lumbar area) carries most of an employee’s weight, it is usually the first damaged area of his or her back. However, back disorders can also occur in the upper (cervical) and middle (thoracic) part of the back.
Simply put, back disorders result from exceeding the capability of the muscles, tendons, discs, or the cumulative effect of several contributors, including, but not limited to:
- Heavy lifting;
- Repetitive lifting;
- Lifting awkward loads;
- Lifting with forceful movement;
- Twisting while lifting;
- Bending while lifting and lifting below the knees;
- Reaching while lifting and lifting above the shoulders;
- Lifting at arms’ length instead of close to the body;
- Sudden movements;
- Pushing and/or pulling;
- Whole-body vibration;
- Staying in one position (including sitting or standing) or bending for too long;
| - Poor footing, such as on slippery floors;
- Hot environments, which can lead to fatigue;
- Cold environments, which can decrease blood flow and muscle strength;
- Inadequate lighting or blocked views, which can lead to awkward postures;
- Poor physical condition, being overweight, stress, or aging;
- Poor body mechanics or poor posture (slouching);
- Poor job or work area design;
- Fast work pace and excessive workload demands;
- Long hours and infrequent breaks; and
- Fatigued muscles.
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In broader terms, the major contributing factors associated with the development of back disorders include:
- Physical factors (e.g., physical demands of the job);
- Ergonomic risk factors:
- Repetitive motion (e.g., frequent reaching, lifting, or carrying);
- Awkward postures (e.g., bending, twisting, reaching, working overhead, or holding fixed positions);
- Forceful exertion (e.g., carrying or lifting heavy loads or pushing a loaded pallet jack);
- Static postures (e.g., maintaining fixed positions for a long time);
- Vibration (e.g., whole-body vibration from sitting or standing on surfaces that vibrate such as vehicles, equipment, or platforms); and
- Contact pressure (e.g., grasping or contact from loads or leaning against parts or surfaces that are hard or have sharp edges);
- Environmental factors (e.g., hot/cold temperatures and high/low lighting);
- Individual factors (e.g., age, stature, medical conditions, and recreational activities); and
- Work organization factors (e.g., fast work pace, low-staffing levels, shift work, or lack of rest breaks).
When warehouse or storage facility employees are exposed to more than one of these, the chances of developing back disorders increase. Therefore, identifying all the contributing factors present at your facility is essential to reduce back disorders.
Did You Know
Reaching and lifting, or carrying a 10-pound object that is 10 inches from the spine is equal to 100 pounds of force on the lower back. Reaching and lifting, or carrying a 10-pound object that is 25 inches from the spine is equal to 250 pounds of force on the lower back.
Back Hazard Identification
It’s hard to prevent back disorders or control back hazards until you first identify the back hazards in your warehouse or storage facility. However, you don’t want to simply wait for a problem to surface. Be proactive. The following steps may help you determine if you need to look further at back safety and health and to what extent it poses a problem at your location.
Written Records Review
A records review can tell you the total number of back disorders reported to management; the date each case was reported; the department or specific job of those who were injured; and the number of employees on the same job or in the same department. This review can also help you spot any trends with back disorders. Records to review might include:
- OSHA logs;
- Employee reports and complaints;
- Workers’ compensation reports;
- Facility medical records (if you have the proper access rights or permissions);
- Accident reports and investigations;
- Time cards revealing hours worked each day, when rest breaks were taken, and any sick days; and
- Payroll records, which can be used to determine the number of hours worked.
Observation of Work Activities
A walk around your warehouse or storage facility should give you firsthand information about back hazards for your employees. During a walkaround:
- Observe employee postures and lifting;
- Determine the weight of objects lifted;
- Determine the frequency and duration of lifting tasks;
- Measure the dimensions of the workplace and loads; and
- Look at the layout of the warehouse or storage areas to see if this plays a factor.
Also pay attention to warning signs, such as:
- Risk factors in work tasks (e.g., repetitive motions, awkward postures, forceful exertions, staying in the same position for a long time, whole-body vibration, and contact pressure points);
- Employee fatigue, discomfort, or reports of related problems;
- Employees exhibiting “pain-related behaviors” (e.g., not moving body parts, self-restricting their movements, or massaging necks, or backs);
- Employees modifying tools, equipment, or workstations on their own;
- Increases in absenteeism, employee turnover rates, or customer complaints;
- Decreases in product or service quality or employee morale;
- Increases in error rates, rejects, or wasted materials;
- Work bottlenecks;
- Malfunctioning equipment;
- Missed deadlines; and
- Unnecessary handling of material and product movement.
Employee Interviews and Surveys
Talk to employees, supervisors, and managers about where problems exist. Ask employees about their opinion on the difficulty of tasks as well as personal experiences of back pain. Also, ask them about their ideas for altering work processes, operations, tools, or equipment, and find out how they would make their jobs less physically demanding and more efficient.
Employee surveys may assist in identifying new or early cases of back disorders in the work force. They’re useful in smaller facilities where data gathered from records reviews may be limited or in facilities where reporting disincentives limit the number of reported cases. The major reason for a survey is to collect data on the number of employees that may be experiencing some form of back injury or disorder. This is also a good method for identifying departments or jobs where potential back problems exist. Things to consider in designing a questionnaire or symptom survey, include the following:
- Reading level and primary language of employees if the questionnaire or survey is self-administrated. Wording is very important and must be geared to particular respondents.
- Length of the questionnaire (usually should not exceed 20 minutes).
- Instructions should be clear.
- Important questions should be asked first.
- Sensitive or personal questions should be asked later in the survey.
- Multiple-choice questions are easier to evaluate but limit the potential responses of the person being questioned.
Consider asking your employees for examples of tasks they perform that: require lifting at your site or involve ergonomic risk factors.
Evaluate Specific Jobs and Tasks
To determine where problems may arise in work tasks at your warehouse or storage facility, you may want to use a checklist to find problem jobs, screen jobs for risk factors, perform job safety analysis, and/or apply some popular assessment tools.
Checklists
The NIOSH Hazard Evaluation Checklist for Lifting, Carrying, Pushing, or Pulling can be used as a screening tool to provide a quick determination as to whether or not a particular job task is comprised of conditions that place the employee at risk of developing low back pain. The NIOSH Materials Handling Checklist, on the other hand, is a tool to quickly identify potential problem jobs. Neither checklist is designed to be a comprehensive risk assessment technique. Additional risk factors may exist that are not accounted for in these checklists. It is common practice to follow up checklist observations with more precise techniques to confirm problem risk factors.
| NIOSH Hazard Evaluation Checklist for Lifting, Carrying, Pushing, or Pulling |
| “Yes” responses are indicative of conditions that pose a risk of developing low back pain; the larger the percentage of “YES” responses, the greater the risk. |
- General risk factors
| Yes | No |
- Does the load handled exceed 50 pounds?
| Yes | No |
- Is the object difficult to bring close to the body because of its size, bulk, or shape?
| Yes | No |
- Is the load hard to handle because it lacks handles or cutouts for handles, or does it have slippery surfaces or sharp edges?
| Yes | No |
- Is the footing unsafe? For example, are the floors slippery, inclined, or uneven?
| Yes | No |
- Does the task require fast movement, such as throwing, swinging, or rapid walking?
| Yes | No |
- Does the task require stressful body postures such as stooping to the floor, twisting, reaching overhead, or excessive lateral bending?
| Yes | No |
- Is most of the load handled by only one hand, arm, or shoulder?
| Yes | No |
- Does the task require working in environmental hazards, such as extreme temperatures, noise, vibration, lighting, or airborne contamination?
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- Does the task require working in a confined area?
| Yes | No |
- Specific risk factors
| Yes | No |
- Does the lifting frequency exceed 5 lifts per minute (LPM)?
| Yes | No |
- Does the vertical lifting distance exceed 3 feet?
| Yes | No |
- Do carries last longer than 1 minute?
| Yes | No |
- Do tasks that require large sustained pushing or pulling forces exceed 30 seconds duration?
| Yes | No |
- Do extended reach static holding tasks exceed 1 minute?
| Yes | No |
| NIOSH Materials Handling Checklist |
| “No” responses indicate potential problem areas which should receive further investigation. |
| 1. Are the weights of loads to be lifted judged acceptable by the workforce? | Yes | No |
| 2. Are materials moved over minimum distances? | Yes | No |
| 3. Is the distance between the object load and the body minimized? | Yes | No |
| 4. Are walking surfaces level? | Yes | No |
| .................... wide enough? | Yes | No |
| .................... clean and dry? | Yes | No |
| 5. Are objects easy to grasp? | Yes | No |
| .................... stable? | Yes | No |
| .................... able to be held without slipping? | Yes | No |
| 6. Are there handholds on these objects? | Yes | No |
| 7. When required, do gloves fit properly? | Yes | No |
| 8. Is the proper footwear worn? | Yes | No |
| 9. Is there enough room to maneuver? | Yes | No |
| 10. Are mechanical aids used whenever possible? | Yes | No |
| 11. Are working surfaces adjustable to the best handling heights? | Yes | No |
| 12. Does material handling avoid: | Yes | No |
| .................... movements below knuckle height and above shoulder height? | Yes | No |
| .................... static muscle loading? | Yes | No |
| .................... sudden movements during handling? | Yes | No |
| .................... twisting at the waist? | Yes | No |
| .................... extended reaching? | Yes | No |
| 13. Is help available for heavy or awkward lifts? | Yes | No |
| 14. Are high rates of repetition avoided by job rotation? | Yes | No |
| .................... self-pacing? | Yes | No |
| .................... sufficient pauses? | Yes | No |
| 15. Are pushing or pulling forces reduced or eliminated? | Yes | No |
| 16. Does the employee have an unobstructed view of handling the task? | Yes | No |
| 17. Is there a preventive maintenance program for equipment? | Yes | No |
| 18. Are employees trained in correct handling and lifting procedures? | Yes | No |
Screening Jobs for Risk Factors
Efforts to identify jobs or tasks having known risk factors for back disorders can provide the groundwork for changes aimed at risk reduction. Even without clear medical evidence, screening jobs for ergonomic risk factors can offer a basis for early interventions. Remember that the ergonomic risk factors include: repetitive motion, awkward posture, forceful exertion, static posture, vibration, and contact pressure.
The purpose of the following worksheet is to increase basic awareness of potential problems associated with jobs and tasks. This awareness can help provide clues on how to make effective improvements.
| Screening Jobs for Back Disorder Risk Factors |
Job Title: _____________________________ Job Location: __________________________________
Name of Employee: __________________________________________________________________
Name of Observer: __________________________________ Date: ____________________________ |
| Risk Factors: | Other clues: | Reasons for Problems: |
| Task 1: |
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Job Safety Analysis
Each job in which employees have a greater incidence of back disorders should be subject to a job safety analysis (JSA), also known as a job hazard analysis (JHA). A JSA 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. This information is gathered by talking with employees and observing them at work — much like the work activity observations and employee interviews and surveys discussed earlier. However, JSAs are now focused on a particular job to be analyzed.
Talking to employees to get insight into the job requirements provides information that only those who work at the job can provide. It is often the best way to identify the causes of the problem and to identify the most cost-effective solutions to it. Whether you talk to employees while observing them, talk to them at a staff meeting, or ask them to fill out a questionnaire, any of these methods can be effective. However, be sure to pose the questions in a way to minimize bias. For example, the following questions tend to elicit useful information and do not prejudge the answer:
- Are parts of your job more difficult than others?
- Does your injury hurt more when performing certain tasks?
- Could you recommend improvements to the job?
Another important part of JSA is observing employees performing the job to identify the risk factors in the job and to evaluate the magnitude, frequency, and duration of exposure to those risk factors. Observing employees at work is important because it allows you to see precisely which tasks may be imposing biomechanical stress on the individual. Observation is also necessary because some things may be overlooked in a discussion, or employees may not remember to mention certain activities, particularly those that are short term.
You may wish to use a video camera during observations for subsequent slow-motion analysis later. Use still photos to capture work postures, workstation layouts, tools, etc. While observing an employee perform job tasks, you should:
- Notice what the employee is doing to make himself or herself more comfortable in the workplace. For example, look for improvised foot rests, padding, or homemade tools and devices.
- Record the movements and body mechanics used to perform the task.
- Watch for repeated motions; awkward loads; the position of the arms, wrist, and trunk, such as over-stretching or unusual posture; excessive bending or twisting; lifting below the knees or above the shoulders; poor body mechanics, such as bending at the waist; forceful exertions including lifting, pushing, and pulling; prolonged activities/postures; and vibration.
- Weigh and measure the dimensions of loads.
- Determine the characteristics of work surfaces and/or seating, such as slip resistance, hardness, surface edges, and support.
- Look to see whether the work space is too restrictive or provides inadequate clearances.
- Measure exposures to heat, cold, and whole-body vibration.
- Consider making biomechanical calculations (e.g., the 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).
- Consider taking physiological measures (e.g., oxygen consumption and heart rate).
- Ask questions to determine if staffing levels and production pace is truly representative of the normal operation. Obtain production data if at all possible.
Assessment Tools
The following methods are comprehensive tools designed to provide a detailed analysis of various types of manual material handling tasks. They can be used to evaluate lifting, lowering, pushing, pulling, carrying, and other activities:
- NIOSH Lifting Equation — The NIOSH Lifting Equation is a tool used to evaluate manual lifting tasks. This equation allows you to insert the exact conditions of the lift (e.g., height, distance lifted, weight, position of weight relative to body, etc.). This equation accounts for asymmetrical lifts and objects that are difficult to grasp. See www.cdc.gov/niosh/docs/94-110/.
- ACGIH Threshold Limit Values (TLVs) for Lifting — The American Conference of Governmental Industrial Hygienists (ACGIH) recommends guidelines for safe lifting. The Threshold Limit Values (TLVs) for lifting recommend upper and lower limits based upon frequency, duration, and other risk factors associated with lifting. The following ACGIH Publications may be helpful:
- TLVs and BEIs (#0106), and
- Lifting: TLV Physical Agents(7th Edition) Documentation (#7DOC-734).
- Ohio State Lumbar Motion Monitor — Traditionally, most workplace ergonomic assessments have focused on joint loading in static postures. However, epidemiologic studies have shown that three-dimensional dynamic motion is associated with an increased risk of occupational injury and illness. The Biodynamics Lab has developed a unique research program that focuses on the study of occupational joint loading under realistic dynamic motion conditions. The program’s goal is to obtain a better understanding of how much exposure to realistic risk factors is too much. See http://biodynamics.osu.edu/research.html.
- Snook’s Psychophysical Tables — These tables are based on psychophysical data and provide the maximum acceptable weights and forces for various common tasks including lifting and lowering weights, pulling and pushing forces, and carrying objects. Values are given for different lift heights, number of lifts per minute, and percentiles of male and female populations capable of the task. See S. H. Snook, and V. M. Ciriello. “The Design of Manual Handling Tasks: Revised Tables of Maximum Acceptable Weights and Forces.” Ergonomics 34(9): 1197-1213 (1991).
Did You Know
The National Institute for Occupational Safety and Health (NIOSH) updated its Application Manual for the Revised NIOSH Lifting Equation in September 2021. The update corrects typographical errors from the previous 1994 version, improves graphics and tables, and is reformatted to be searchable. The essential contents of the manual have not changed. Source: DHHS (NIOSH) Publication Number 94-110.
Enforcement Note
OSHA will cite employers for ergonomic hazards associated with repetitive motion and lifting. That’s the takeaway from a $27K fine issued to an employer in December 2021. Workers in the case were performing repeated manual lifts of boxes 50 to 90 pounds from a conveyor to pallets.
The agency cited under the General Duty Clause of the OSH Act and explained that the NIOSH Revised Lifting Equation revealed a lifting score of 7.8, where scores over 3 are considered hazardous. According to OSHA, the employer also failed to record eight work-related musculoskeletal disorders, a violation of 29 CFR 1904.4.
Back Disorder Prevention and Hazard Control
To reduce or eliminate contributing factors for back disorders and improve the fit between the employee and the task, you will want to make ergonomic improvements. Ergonomics is an applied science concerned with arranging the work environment to fit the person so that he or she will interact most effectively and safely. Work tasks should be designed to limit exposure to ergonomic risk factors and fit the capabilities of your employees.
Prioritize Jobs
Decide which tasks to improve and then set priorities. Consider:
- The frequency and severity of the risk factors you have identified that may lead to injuries;
- The frequency and severity of complaints, symptoms, and/or injuries;
- Technical and financial resources at your disposal;
- Employee ideas for making improvements;
- Difficulty in implementing various improvements; and
- Timeframe for making improvements.
Engineering Controls
OSHA’s preferred approach to prevention of injuries and illnesses, including back disorders, is to eliminate the hazardous condition in the workplace, primarily through engineering controls. These include rearranging, modifying, redesigning, providing or replacing tools, equipment, workstations, packaging, parts, processes, products, or materials. Examples of engineering controls in situations involving lifting or manual handling tasks might include the following:
| Raise Height of Loads or Employees |
- Use a small scissors lift cart, load lifter, or pneumatic lifter to raise or lower the load so that it is level with the work surface. Then slide the load instead of lifting.
- Raise the employee with a step stool, portable steps, catwalks, or portable and stackable platforms so that the load is grasped 30 to 40 inches from the surface on which the employee is standing.
- Raise or lower the work surface using stacked pallets, an electric or pneumatic scissor lift, powered stackers, or mobile or stationary scissors lifts. A palletizer can be placed on the forks of a pallet jack to keep product at waist height.
- Make available a variety of work surface heights for employees to choose from.
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Caution
When using portable steps, stools, catwalks, or other work platforms, employees should follow all manufacturers’ recommendations for proper use. They should use only equipment appropriate to the weight, size, and shape of the load being handled.
| Place Storage at Optimum Heights |
- Store heavier or bulkier loads so they can be handled between shoulder and knee height, where employees have the greatest strength and most comfort.
- Use elevated rack locations as the overstock storage area. Pallets of product should then be lowered to more appropriate heights prior to being selected. Selections should be performed with arms close to the body.
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| Add Supports |
- Add extra handles for better grip and control.
- Provide handhold cutouts on all heavy products.
- Use a screen over the opening of a container to support a sack, then pour the contents of the sack through the screen.
- Support containers on or against a fixed object, rack, or stand while pouring contents.
- Use a pail tipper.
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| Provide Better Access |
- Use a turntable. Storage pallets can be placed on turntables for optimal access. Rotate the turntable to bring the load closer. Always have employees work from the side closest to the load. The turntable can also be placed on a load leveler or cart.
- Utilize a turntable in bays so pallets can be rotated to ensure that the product is close to the aisle prior to lifting.
- Develop a product rotation process where pallets are regularly turned 180 degrees using a forklift or pallet truck after the majority of product has been removed.
- Raise the bottom level of racking so loads are at heights where torso bending is not necessary.
- Raise the height of the upper racks to provide more head room to retrieve loads on the lower racks.
- Tilt containers to improve handling of materials. Fixed, adjustable, and powered tilt stands are available.
- Consider angled shelving to improve access to containers or loads.
- Install tilted flow racks to bring boxes to the front of shelves.
- Remove or lower the sides of a receptacle or use bins with flip-down sides.
- Use a cutout work surface so the employee can get closer to the load that rests on the surface.
- Use roller and channel devices to allow the load to be pulled out for better access.
- Provide wider slots, especially for heavier product, so employees can walk into the slot and access all sides of the pallet. Providing full slotting, especially for product that is heavy or bulky, will give employees better access without undue reaching or bending.
- Create space around palletized loads so employees can access product from the side, keeping it close to the body prior to lifting.
- Increase the width of aisles where fast-moving product is located. This will allow more pallet jacks to get closer and will reduce the distance that loads must be carried.
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| Use a Tool |
- Use a hook (also known as a “pick stick” or “Bow Peep hook”) to pull small, light-weight loads closer to the edge, to reduce an employee’s reach.
- Use a sticker dispenser that can be worn around the employee’s waist. This device will allow employees to use both hands when lifting product.
- Provide a clipboard on the pallet jack to hold the sticker sheets rather than having employees hold the sheets in their hand while lifting.
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| Use Non-powered Equipment |
- Use a drum dolly, two-wheel dolly, hand cart, platform truck, portable scissors lift cart, hand truck, or hand pallet truck.
- Use a conveyor, slide, or chute whenever possible.
- Use a portable hoist or crane. A hoist may be able to lift more loads at one time.
- Place a slip sheet made of low friction material on partially emptied layers to facilitate sliding of product from the back of the pallet.
- Instead of lifting and pouring from a drum, insert a siphon or a pump.
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| Use Powered Equipment |
- Use powered equipment like a stacker, powered hand truck, airball table, forklift, crane, pallet truck, drum lifter, manually propelled load lifter, vertical/horizontal carousels, or industrial tilter.
- Use a vacuum lifter. The strong suction of a vacuum lifter can lift up to 150 pounds.
- Provide a pallet dispenser to reduce handling of pallets. This device allows employees to drive their pallet jack to the dispenser. An empty pallet is then automatically loaded onto the forks without manual lifting.
- Use an automatic plastic wrapping machine with palletized product sitting on a turntable. This ensures the employee will not have to bend at the waist to wrap the pallet.
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| Work with Suppliers |
- Work with suppliers to provide product in smaller, lighter containers.
- Encourage suppliers to provide product in stable boxes with handhold cut-outs or handles. This is especially important for product that is extremely heavy.
- Work with suppliers to ensure that container integrity will be adequate so a box, bag, or bucket will not accidentally break, rip, or pull apart during lifting operations.
- Work with suppliers to get a slip sheet between the layers on a pallet. This will decrease the force needed to slide product toward the employee. This is especially helpful with products like bagged product.
- Have suppliers wrap only the sides and tops of cases, leaving the cardboard bottom exposed to facilitate sliding.
- Request that suppliers provide product on lighter, plastic pallets. The employees of both your warehouse and the supplier will benefit from the reduction in weight. Plastic pallets easily nest together to reduce the space of stacking. They also eliminate splinters and uneven surfaces that employees may step on when walking over pallets.
- Ask the supplier to box, not bag product. Boxes are easier to slide than bagged product and boxes are usually packaged in smaller quantities so the overall package is lighter.
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Did You Know
Wooden pallets weigh between 40 and 70 pounds and may be lifted several times during a work shift. This repeated lifting can cause stress to the lower back. A plastic pallet weighs about 20 pounds, so the difference is significant.
| Other Engineering Control Methods |
- If manual wrapping must be performed, use rolls that weigh as little as possible to minimize the lifting hazard.
- Increase the weight of the load using a bulk loading system, so no one would try lifting the load by hand.
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Caution
Just because something is called “ergonomic” doesn’t necessarily mean it will work for your situation.
Administrative Controls
Engineering controls are the most desirable, where possible. However, administrative or work practice controls may be appropriate in some cases where engineering controls cannot be implemented or when different procedures are needed after implementation of the new engineering controls. Administrative controls should not be viewed as primary methods of control.
Consider the following administrative control methods for your warehouse or storage operation:
- Alternate heavy tasks with light tasks.
- Require that heavy loads only be lifted by two employees, in order to limit force exertion.
- Provide variety in jobs to eliminate or reduce repetition (i.e., overuse of the same muscle groups).
- Adjust work schedules, work pace, or work practices.
- Factor in the time it takes for proper work practice, when setting time limits. Time limits should not force employees to use shortcuts like reaching across a pallet instead of walking around the pallet for better access.
- Provide recovery time (e.g., short rest breaks).
- Staff “floaters” to provide periodic breaks between scheduled breaks.
- Rotate employees through jobs that use different muscles, body parts, or postures.
- Minimize overtime if at all possible.
- Provide part-time staff for peak periods.
- Schedule overtime on off-days instead of extending the regular work shift. This will allow a period of recovery between shifts when employees may recuperate.
- Assign any required overtime on a volunteer basis as much as possible.
- Institute physical conditioning or stretching programs to reduce the risk of muscle strain.
- Gradually introduce new employees who are not used to the physical demands of the job to a normal work pace and workload like an athlete in spring training.
- Gradually introduce those returning from long absences to a normal work pace and workload.
Administrative controls, such as job rotation, can help reduce employees’ exposures to risk factors by limiting the amount of time employees spend on “problem jobs.” However, these measures may still expose employees to risk factors that can lead to back disorders. Therefore, the most effective way to eliminate “problem jobs” is to change them. This can be done by putting into place the appropriate engineering controls and modifying work practices accordingly.
Did You Know
There are hundreds of ideas for reducing lifting available in the Ergonomics Ideas Bank, found at www.ergoideas.Lni.wa.gov. These ideas have been reviewed by a team of ergonomists, so the ideas have some credibility.
Work Practice Controls
Work practice controls, another method for controlling back hazards, reduce the likelihood of exposure to hazards by addressing the manner in which a task is performed.
Proper Posture
To put the least amount of stress and strain on the muscles and bones, warehouse and storage facility employees should use these posture techniques:
- Standing: Tuck in the chin and relax the shoulders. Keep the feet at least a foot apart. Stand with one foot on a small stool and switch feet. Move about whenever possible.
- Sitting: Keep the head directly over the shoulders. Relax the shoulders. Ensure the chair back is supporting the lower back. Keep the knees at the same level as the hips or slightly lower. Sit as close to the work as possible.
Proper Lifting
Many low back strains and injuries can be avoided by this basic procedure for good lifting:
- Size up the load before trying to lift it. Test the weight and stability by lifting at one of the corners. Get help or use a device if the load is too heavy.
- Make sure the load can be carried to its destination before attempting the lift. Make sure the path is clear and safe.
- Bend the knees. Place the feet apart and close to the object. Center the body over the load, then bend the knees.
- Get a good hand hold. Use both hands when possible.
- Lift straight up, smoothly and evenly. Avoid jerking. Use extra caution when lifting loads that may be unstable. Do not bend at the waist. Allow the legs to do the work.
- Do not twist or turn the body once a lift is made. If a turn is necessary, do so by changing foot positions, stepping to one side or the other to turn.
- Keep the load steady and close to the body. Do not carry a load above the head, below the knees, or on the side of the body. Keep a clear view of the path.
- Set the load down properly. Bend the knees, keeping the back upright, letting the legs do most of the work. Do not let go of the load until it is on the floor.
- Always push an object, rather than pull it. Pushing puts less strain on the back and is safer should the object tip.
The proper lifting procedure is slightly different when lifting a heavy sack from the floor:
- Kneel down on one knee. Keep the foot of the other leg flat on the floor.
- Lean the sack onto a kneeling leg.
- Slide the sack onto the kneeling leg.
- Slide the sack onto the top of other leg close to the body at waist level.
- Stand up, keeping the sack close to the body.
Other Work Practice Controls
Beyond proper posture and lifting, other safe work practice controls might include the following:
- Loading pallets with lighter product in the center and heavier product on the outer edges to ensure easier access and lifting of the heavier items;
- Performing warm-up exercises prior to lifting tasks;
- Choosing a glove size that fits properly if gloves are worn;
- Wearing appropriate shoes to avoid slips, trips, or falls;
- Inspecting pallets before loading or moving them;
- Testing the load for stability and weight;
- Reducing the load to move heavy loads over long distances;
- Using the buddy system for heavy or awkward lifts;
Training Tip
Advise employees that if it’s a long load, they should get some help. Long objects, such as pipes or lumber, may not be heavy, but the weight might not be balanced and such lifting could result in back sprain.
Also let employees know that very heavy loads should be split into several smaller loads. Or if the load cannot be split, advise them to use the buddy system or a mechanical assist. One person trying to lift a heavy load may be asking for trouble.
Note that while team lifts can reduce the load in half, they also increase the risk of a slip, trip, or fall accident. It’s a good idea to discuss the lift before doing it so team members don’t make surprise movements. If possible, employees should try to find a buddy of similar height to help with the lift.
- Knowing how to use mechanical assist equipment properly;
- Pushing instead of pulling, when there is a choice;
- Carrying only as much as the employee can safely handle;
- Pushing or pulling equipment with the entire body, instead of with just the arms and shoulders;
- Using both hands when pushing or pulling if feasible;
- Sliding, pushing, or rolling a load, instead of carrying it when appropriate;
- Avoiding slopes, stairs, or other obstacles that make carrying materials more difficult;
- Avoiding slippery floors;
- Alternating hands when loads must be carried with one hand;
- Alternating heavy lifting with less physically demanding tasks; and
- Taking rest breaks.
Caution
Gloves have advantages and disadvantages. While gloves with rubber dots or rubber palms/fingers on the surface can increase grip stability on slippery load surfaces, a single pair of heat-resistant gloves can reduce grip strength up to 40 percent. Two pairs at once can reduce grip strength up to 60 percent.
Refusal to Lift Program
Some employers have instituted a refusal to lift program. You may wish to consider this approach for your warehouse or storage operations. Under this program, an employee may refuse to perform a lift if he or she feels in good faith that:
- He or she will be exposed to an unacceptable risk of a back disorder,
- The load itself will be subject to damage,
- He or she lacks the training necessary to perform the lift safely,
- He or she lacks a properly trained lift team necessary to perform the lift, or
- He or she lacks the proper lifting device or equipment necessary to perform the lift.
No disciplinary action would be taken if one of the criteria above are met. However, this employee must immediately notify a designated person of the refusal, so that the designee can determine if the lift is necessary and how the lift can be done safely.
Training
Training alone will not always prevent back disorders. Training should be used together with any workplace controls implemented. Warehouse and storage facility employees need training and hands-on practice with new tools, equipment, or work practices to make sure they have the skills necessary to work safely.
Training on safe lifting techniques and generally safe work practices to protect the back should be an element of any back safety program. Communicating to employees the hazards of certain types of movements and methods to avoid them can significantly reduce those high-hazard practices and cut down on back pain and injury.
Employee training should go over:
- Back hazards and their causes;
- Proper use of equipment and how employees should perform tasks (proper posture/lifting);
- Stretching and warm-up exercises to be performed prior to lifting tasks;
- How to recognize symptoms of back disorders; and
- Who to contact to report hazards and back disorders.
Training could also include how to:
- Plan ahead when lifting jobs are necessary;
- Get help to lift objects that are too heavy;
- Never twist or turn suddenly while carrying a load;
- Reduce the vertical and horizontal lifting distances;
- Reduce the reach distances;
- Make sure the path is clear before picking up the load, and to take careful steps;
- Lift with the legs and not with the back;
- Maintain proper posture when standing, sitting, or reclining; and
- Follow a sensible diet and exercise program for overall good health.
Training Tip
Stretching, for example, can make the back stronger, more flexible, and more resistant to injury. Have employees work on these muscles: back, thighs, buttocks, and hamstrings. Have them bend and stretch those muscles, holding them for at least 15 seconds, without bouncing.
A proper diet can also prevent injury. Suggest that employees:
- Drink 6 to 8 glasses of water a day to reduce tearing injuries and prevent stiffness.
- Eat a well-balanced diet to receive energy. Injuries often occur when a person is mentally and physically tired.
- If they have back pain, they should decrease caffeine intake. Caffeine increases muscle sensitivity to pain.
Training is most effective when it is interactive and fully involves employees. Below are some suggestions for training based on adult learning principles:
- Provide hands-on practice when new tools, equipment, or procedures are introduced to the workforce.
- Use several types of visual aids (e.g., pictures, charts, and/or videos) of actual tasks in your workplace.
- Hold small-group discussions and problem-solving sessions.
- Give employees ample opportunity for questions.
Make sure that employees have learned what you’re trying to teach them, by having each one of them demonstrate the lifting techniques properly before leaving the class. Also, be sure to follow-up with employees to make sure they are able to use the techniques on the job.
Enforce the lifting methods that are taught. The accident rates for lifting injuries speak for themselves, so employees should be taught to think of improper lifting as a dangerous activity. You don’t allow floors to accumulate grease, and you don’t allow ladders with missing rungs to be used. By the same token, you should not allow poor lifting techniques to pass unnoticed.
Personal Protective Equipment
Personal protection solutions have only limited effectiveness when dealing with ergonomic hazards. Personal protective equipment (PPE) is used as a barrier between the contributing factors and the employee. PPE should be the last resort used to reduce employees’ exposure to contributing factors and not serve as a substitute for other feasible improvement options. Nevertheless, it is important to provide this type of protection to employees when appropriate.
Obtain the active involvement of employees in the selection, care, and maintenance of PPE. Find out from the employees whether the PPE will interfere with effective workplace performance. Make sure PPE is properly fitted, worn, and maintained.
PPE may include a combination of gloves, safety shoes or boots, and other appropriate protective equipment. Before providing PPE to employees, be sure that they are properly trained in its use.
Gloves
While gloves can protect the hands from hand injury, it is important to know that:
- Gloves with rubber dots or rubber palms/fingers on the surface may enhance the grip on slippery load surfaces.
- If gloves are too large, they may make it harder to grip.
- A single pair of heat-resistant gloves can reduce grip strength up to 40 percent.
- Two pairs at once can reduce grip strength up to 60 percent.
Provide gloves in different sizes to ensure that each employee can select a pair that fits properly. When employees must grip on a low-friction surface, provide gloves that enhance the grip, such as those with rubber dots or strips. Remember that some employees may have an allergic reaction to gloves made of latex or natural rubber.
Safety Shoes and Boots
Warehouse and storage facility employees may be on their feet for long periods of time, possibly an entire shift. The leg muscles continually support the body, which can cause fatigue. These employees also work on hard concrete surfaces, which can create contact trauma or tendon and muscle problems if proper footwear is not worn.
However, shoes with solid support, flex at the ball of the foot, and adequate padding will maintain foot support and provide shock absorption against foot strike while walking on hard concrete surfaces. Provide employees with padded shoe inserts that support the foot and cushion against foot strike. These anti-fatigue soles and insoles can also reduce fatigue after long hours of standing on hard surfaces.
Did You Know
The National Occupational Research Agenda (NORA) suggests workers check their shoes and replace them before serious wear occurs. NORA explains that if the width of the area of wear on the bottom of a shoe is smaller than the base of a AA battery, the shoe is still good. However, if the worn area is wider than the base of the AA battery, it’s time to replace the shoes, NORA says.
Shoes with non-skid soles are also important, particularly where surfaces are potentially slippery. Several shoe manufacturers have developed rubber-type soles that are specifically designed for working in a wet environment.
Other safety shoes and boots (steel toe, for example) are designed to protect the feet from blunt injury.
Back Support Belts
In recent decades, back support belts have been introduced to general industry after a history of use in the sport, weight lifting. These belts are also known as weight lifting devices, supports, aids, and abdominal belts. However, according to an April 6, 1998, OSHA letter of interpretation, back belts are not recognized by OSHA as effective controls to prevent back injury. While the belts may be accepted by individual employees because they feel as if they provide additional support, the effectiveness of back belts in the prevention of low back injuries has not been proven in the work environment. The OSHA interpretation adds that the agency does not forbid the use of back belts and similar devices, nor does it endorse their use.
Caution
Studies from the NIOSH do not confirm that using back belts are beneficial. In particular, the NIOSH study, “Workplace Use of Back Belts”:
- Could not conclude that back belts lessen risk of injury;
- Does not recommend the use of back belts to prevent injuries among uninjured employees;
- Emphasizes that back belts do not mitigate the hazards to employees posed by repeated lifting, pushing, pulling, twisting, or bending; and
- Does not consider back belts to be PPE.
Keep in mind that a back support belt can never take the place of good body mechanics or proper lifting techniques.
Back Disorder Reports and Management
Comprehensive injury reporting is important to the success of a back safety program. The goal of this effort is to properly assess, diagnose, and treat back disorders. Early reporting, diagnosis, and intervention can limit injury severity, improve the effectiveness of treatment, minimize the likelihood of disability or permanent damage, and reduce workers’ compensation claims. This will allow the employer to correctly identify work areas or specific tasks where injuries frequently occur or are most severe. This information helps direct your safety efforts, as well as to guide healthcare providers in making return-to-work and light-duty work decisions. OSHA’s injury and illness recording and reporting regulation (29 CFR 1904) requires employers to record and report work-related injuries and illnesses.
Encouraging and utilizing reports of back disorder symptoms:
- Reinforces employee training on recognizing back disorder symptoms;
- Encourages early reporting of back disorder symptoms;
- Allows for prompt medical evaluations for diagnosis, treatment, and follow-up care;
- Reduces injury severity, the number of workers’ compensation claims and associated costs, and the likelihood of permanent disability;
- Provides guidance on return-to-work and work placement restrictions during the healing process;
- Guides job modifications;
- Provides a mechanism to track and trends related to back disorders; and
- Enables assessment of the effectiveness of control measures.
Healthcare professionals are important because they help injured employees recover more quickly and return to their jobs with appropriate restrictions and less risk for re-injury. Work accommodations and alternative duty tasks will help employees recover faster, so that they can return to their usual job without restrictions and risk of re-injury. It is necessary that healthcare professionals are knowledgeable about the operations and work practices within the warehousing and storage industry. Their knowledge will allow them to assist the injured employee during the healing process and in post-injury work placement.
Did You Know
Back disorders are one of the leading causes of disability for people in their working years.
Whenever you determine that an employee has suffered a back disorder incident, you should follow these steps:
- Respond promptly to prevent the employee’s condition from getting worse.
- Provide the employee with prompt access to a healthcare professional (HCP) for evaluation, management, and follow-up. This HCP should be knowledgeable in the assessment and treatment of work-related back disorders to ensure appropriate evaluation, management, and follow-up of employees’ back disorders.
- Provide the HCP with the information necessary for conducting back disorder management, including:
- A description of the employee’s job and information about the physical work activities, risk factors, and back disorder hazards in the job; and
- A list of information that the HCP’s opinion must contain.
- Instruct the HCP that his/her opinion may not include any findings or information that is not related to workplace exposure to ergonomic risk factors, and that the HCP may not communicate such information to you, the employer, except when authorized to do so by state or federal law.
- Obtain a written opinion from the HCP and ensure that the employee is also promptly provided a copy. This written opinion contains:
- The HCP’s assessment of the employee’s medical condition as related to the physical work activities, risk factors, and back disorder hazards in the employee’s job;
- Any recommended work restrictions, including, if necessary, time off work to recover, and any follow-up needed;
- A statement that the HCP has informed the employee of the results of the evaluation, the process to be followed to affect recovery, and any medical conditions associated with exposure to physical work activities, risk factors, and back disorder hazards in the employee’s job; and
- A statement that the HCP has informed the employee about work-related or other activities that could impede recovery from the injury.
- Communicate with the HCP, and together, promptly determine whether temporary work restrictions or time off are necessary.
Management Support
Management leadership and commitment provides the motivating force and the resources for organizing and controlling activities within an organization. In effective back safety programs, management regards the protection of employee health and safety as a fundamental value of the organization, and incorporates objectives for the success of this program into its broader company goals.
It is the employer’s basic obligation to demonstrate leadership by developing ways for employees to report back disorders, responding promptly to those reports, and involving management in the overall back safety program. Ensuring that policies and practices encourage and do not discourage the early reporting of back disorders, their signs and symptoms, back hazards, and employee participation in the back safety program is essential to its success.
Leadership may be demonstrated by participating in plant walkarounds, holding meetings with employees on back safety issues, and monitoring reports on program effectiveness. Involvement that shows commitment to the company’s back safety program can be demonstrated through the following 10 methods:
- Issuing policy statements:
- Treat ergonomic and back safety efforts as furthering the company’s goals of maintaining and preserving a safe and healthful work environment for all employees;
- Expect full cooperation of the total workforce (managers, supervisors, employees, and support staff) in working together toward realizing back safety improvements;
- Assign lead roles to designated persons who are known to “make things happen”;
- Give back safety efforts priority with other cost reduction, productivity, and quality assurance activities; and
- Work to gain the support of the local union or other employee representatives.
- Initiating meetings between employees and supervisors to allow full discussion of the policy and the plans for implementation.
- Setting goals that become more concrete as they address specific operations. Goals give priority to the jobs posing the greatest risk.
- Committing resources to:
- Training employees to be more aware of ergonomic risk factors for work-related back disorders;
- Providing detailed training and instruction for those expected to assume lead roles or serve on special groups to handle various tasks;
- Bringing in outside experts for consultations about start-up activities and difficult issues, at least until in-house expertise can be developed; and
- Implementing control measures as may be indicated.
- Providing release time or other compensatory arrangements during the workday for employees expected to handle assigned tasks dealing with back safety concerns.
- Furnishing information to all those involved in or affected by the back safety activities to be undertaken. Misinformation or misperceptions about such efforts can be damaging: If management is seen as using the program to gain ideas for cutting costs or improving productivity without equal regard for employee benefits, the program may not be supported by employees. For example, management should be up-front regarding possible impacts of the program on job security and job changes. All back injury data, production information, and cost considerations need to be made available to those expected to make feasible recommendations for solving problems.
- Tracking the results of back safety efforts to indicate both the progress that has been made and the plans that need to be revised to overcome apparent problems. Reporting results of the program and publicizing notable accomplishments also emphasize the program’s importance and maintain the interest of those immediately involved and responsible.
- Creating committees or teams to receive information on back safety problem areas, analyze the problems, and make recommendations for corrective action.
- Establishing a procedure to encourage prompt and accurate reporting of signs and symptoms of back disorders by employees so that these symptoms can be evaluated to determine if the report qualifies as an OSHA reportable case.
- Communicating periodically with employees about the back safety program and their concerns about back disorders. Seriously take into consideration their reports of potential problems and suggestions for improving job operations or conditions.
Examine existing policies and practices to ensure they encourage and do not discourage reporting and participation in the back safety program. This is necessary to ensure the early reporting of the symptoms and signs of back disorders, as well as meaningful employee participation in the back safety program.
The objective is that employees must feel free to report back disorder signs and symptoms as early as possible, because doing so prevents further pain and suffering and averts disability, not only for the employee who reports the back disorder but also for others who have comparable jobs. Early attention to back disorder reports will also reduce workers’ compensation and other related costs for that injury. To achieve this objective, all back disorders must be reported so that they can be promptly assessed to determine whether they are the result of a problem job.
Employee Involvement
Employees are a vital source of information about hazards in their workplace. Employees help identify hazards and solve problems. Their involvement can enhance job satisfaction, motivation, and acceptance of workplace changes. There are many different ways warehouse and storage facilities can involve employees in their back safety efforts, including the following:
- Submit suggestions and concerns;
- Identify and report tasks that are difficult to perform;
- Discuss work methods;
- Provide input in the design of workstations, work areas, equipment, procedures, and training;
- Help evaluate equipment;
- Respond to surveys and questionnaires;
- Report back disorders as soon as they occur;
- Participate fully in back disorder case investigations; and
- Participate in task groups withresponsibility for back safety.
Follow Up
It is important to follow up in order to evaluate if your improvements have worked. After a reasonable adjustment period, set a date to follow up on the changes made. Make sure to evaluate each improvement separately for effectiveness. The following questions may be helpful.
Has each improvement:
- Reduced or eliminated fatigue, discomfort, symptoms, and/or injuries?
- Been accepted by employees?
- Reduced or eliminated most or all of the risk factors?
- Caused any new risk factors, hazards, or other problems?
- Caused a decrease in productivity and efficiency?
- Caused a decrease in product and service quality?
- Been supported with the training needed to make it effective?
If you determine that your improvements have not worked, modify them or try something different until the risk factors have been reduced or eliminated.
Evaluation and follow-up help sustain continuous improvement in reducing back disorders, track the effectiveness of specific back safety solutions, identify new problems, and show areas where further attention is needed. Warehouse and storage facility managers can use the same methods they use to identify back disorder concerns (such as OSHA 300 and 301 injury and illness information, workers’ compensation records, employee interviews, and observation of workplace conditions) to evaluate progress. You can also keep a list of activities and improvements to track what has been accomplished and provide data on the effectiveness of the initiatives.
How often you evaluate the program will vary by the size and complexity of the facility. However, a good rule of thumb is to evaluate every three years. Warehouse and storage facility management should revise the program in response to identified deficiencies and communicate the results of the program evaluation and any program revisions to employees.
Acknowledgements
Large portions of the ez Explanations™ and In Depth sections of this topic on back safety for warehousing originate from three publications prepared by the Cal/OSHA Consultation Service, Research and Education Unit, Division of Occupational Safety and Health, California Department of Industrial Relations. These publications include:
- Ergonomic Guidelines for Manual Material Handling, 2007;
- Ergonomics in Action: A guide to Best Practices for the Food-Processing Industry, 2003; and
- Ergonomic Survival Guide for Laborers, 2003.
Similarly, portions also originate from a Washington State Department of Labor & Industries slide presentation, “Lifting Hazards and Some Ideas on How to Reduce Your Risk of Lifting Injury,” created in 2007. In addition, publications and materials from federal OSHA, the National Institute for Occupational Safety and Health (NIOSH), the Bureau of Labor Statistics (BLS), and J. J. Keller & Associates, Inc., are used in this topic.
