Recommended Weight Limit
Safe Lifting Guidelines to Prevent Back Pain, MSDs

Effective ergonomic interventions can lower the physical demands of manual material handling, thereby lowering the incidence and severity of the musculoskeletal injuries they can cause.

Musculoskeletal disorders can result in protracted pain, disability, medical treatment, and financial stress for those afflicted with them, and employers often find themselves paying the bill, either directly or through workers’ compensation insurance, at the same time they must cope with the loss of the full capacity of their workers.

Their potential for reducing injury related costs alone make ergonomic interventions a useful tool for improving a company’s productivity, product quality, and overall business competitiveness. But very often productivity gets an additional and solid shot in the arm when managers and workers take a fresh look at how best to use energy, equipment, and exertion to get the job done in the most efficient, effective, and effortless way possible.

The National Institute of Occupational Safety and Health’s (NIOSH) Lifting Equation provides guidelines for evaluating two-handed manual lifting tasks. It defines a Recommended Weight Limit (RWL) as the weight of the load that nearly all healthy workers can lift over a substantial period of time (e.g., eight hours) without an increased risk of developing lower back pain.

The maximum weight to be lifted with two hands, under ideal conditions, is 51 pounds. The RWL is based on six variables that reduce the maximum weight to be lifted to less than 51 pounds.

Management Guidelines for Safer Lifting

• Plan the workflow to eliminate unnecessary lifts.

• Organize the work so that the physical demands and work pace increase gradually.

• Minimize the distances loads are lifted and lowered.

• Position pallet loads of materials at a height that allows workers to lift and lower within their power zone.

 • Avoid manually lifting or lowering loads to or from the floor.

• Store materials and/or products off the floor.

• Arrange materials to arrive on pallets, and keep materials on pallets during storage. • Use a forklift to lift or lower the entire pallet of material, rather than lifting or lowering the material individually.

• Arrange to have material off-loaded directly onto storage shelves. Store only lightweight or infrequently lifted items on the floor.

• Use mechanical devices (e.g., lifts, hoists) whenever possible.

• Avoid designing jobs that require workers to lift or lower materials to or from floor level.

For loads that are unstable and/or heavy:

• Tag the load to alert workers.

• Test the load for stability and weight before carrying the load.

• Use mechanical devices or equipment to lift the load. Reduce the weight of the load by:

• Putting fewer items in the container.

• Using a smaller and/or lighter-weight container.

• Repack containers so contents will not shift and the weight is balanced. •

 Use team lifting as a temporary measure for heavy or bulky objects. Reduce the frequency of lifting and the amount of time employees perform lifting tasks by:

• Rotating workers in lifting tasks with other workers in non-lifting tasks.

• Having workers alternate lifting tasks with non-lifting tasks.

• Clear spaces to improve access to materials or products being handled. Easy access allows workers to get closer and reduces reaching, bending, and twisting.

Employee Guidelines for Safer Lifting

The use of stretching is appropriate as part of a comprehensive ergonomic program. Stretching must not be used in place of engineering and/or administrative improvements, which may include:

• Checking for tags on loads; and

• Before lifting, always test the load for stability and weight.

For loads that are unstable and/or heavy, follow management guidelines for:

• Equipment use;

• Reducing the weight of the load; and

• Repacking containers to increase stability.

Plan the lift:

• Wear appropriate shoes to avoid slips, trips, or falls.

• If you wear gloves, choose the size that fits properly. Depending on the material the gloves are made of and the number of pairs worn at once, more force may be needed to grasp and hold objects. For example, wearing a single pair of heat resistant gloves can reduce your grip strength up to 40 percent. Wearing two or more pairs of gloves at once can reduce your grip strength up to 60 percent.

• Lift only as much as you can safely handle by yourself.

• Keep the lifts in your power zone (i.e., above the knees, below the shoulders, and close to the body), if possible.

• Use extra caution when lifting loads that may be unstable.

When lifting:

• Get a secure grip;

 • Use both hands whenever possible;

• Avoid jerking by using smooth, even motions;

• Keep the load as close to the body as possible;

• To the extent feasible use your legs to push up and lift the load, not the upper body or back;

• Do not twist your body. Step to one side or the other to turn;

• Alternate heavy lifting or forceful exertion tasks with less physically demanding tasks; and Take rest breaks. FSM Source: National Institute of Occupational Safety and Health.