With an ergonomic lifting aid, in most cases an employee only needs to apply minimal assistive force—typically between 10 and 30 Newton—depending on the device and the application. The weight itself is fully supported by the machine. However, residual forces are always present, and these determine whether a lifting aid is sufficient to ensure a safe and ergonomic workstation. The following sections answer the most frequently asked questions about force, standards, and selecting the right material handling equipment.
What forces remain when using a lifting aid?
A lifting aid completely takes over the weight of a load, but the employee must still apply a guiding force to position, steer, and place the load. This residual effort is not a lifting force, but a horizontal or rotational force required to move the load precisely. This force varies greatly depending on the type of lifting aid and the application.
Specifically, there are three types of residual effort that an employee exerts when working with an ergonomic lifting aid:
- Handling force: the force required to move or rotate the load horizontally
- Positioning Accuracy: Precise Control When Placing an Object in an Exact Position
- Actuation force: operating levers, buttons, or suction cups to grasp or release the load
With a properly adjusted lifting aid, the weight of the load itself no longer puts a strain on the back or shoulders. The remaining strain is primarily felt in the arms, wrists, and hands. This is a fundamental difference from manual lifting, in which the entire weight bears down on the musculoskeletal system.
What determines how much additional effort an employee still needs to put in?
The residual effort required when using a lifting aid is determined by four factors: the type of lifting aid, the system’s range of motion, the nature of the load, and the layout of the workstation. A rigid system with high friction requires more control than a system that moves smoothly with balanced suspension points.
Specific factors that increase residual stress include:
- An object with an uneven distribution of weight that tends to tip over
- Limited range of motion, forcing the employee to steer while in awkward positions
- An outdated or poorly maintained system with increased friction in the rails or the lifting mechanism
- A lifting aid that is not properly adjusted to the weight of the load
A well-designed material-handling solution minimizes these factors by tailoring the lifting aid to the specific workstation and the type of load. The better the fit, the lower the residual effort and the greater the reduction in the physical strain on the employee.
What are the legal standards for lifting weights in the workplace?
In Belgium and the Netherlands, guidelines based on European legislation limit the weight of manual lifts in the workplace. For adult male employees, a maximum manual lifting weight of 25 kilograms is used as the upper limit for occasional lifting. For women, this limit is 15 kilograms. Significantly lower recommended values apply to repetitive lifting.
European Directive 90/269/EEC requires employers to assess and reduce the risks associated with manual lifting. In practical terms, this means that if an employee regularly has to handle loads exceeding these weight limits, the employer is required to provide technical aids. A lifting aid is therefore not only an ergonomic choice but also a legal requirement in many industrial settings.
In addition, other variables also play a role in the risk assessment, such as lifting duration, lifting frequency, lifting height, and distance from the body. Even loads weighing less than 25 kilograms can lead to overexertion if they are lifted frequently, far from the body, or while in a bent posture. Limiting the lifting weight through the use of technical aids is then the appropriate measure.
How does the residual force differ between a vacuum lifter and a mobile lifter?
Both a vacuum lifter and a mobile lifter provide full weight support, but the nature of the effort required differs significantly. A vacuum lifter requires an attendant to guide the load through the space, while a mobile lifter lifts the load to a fixed position, and the employee positions the load rather than guides it.
Vacuum lifter: smooth control, higher lifting force
With a vacuum lifter, the load is secured using suction cups, allowing the operator to move the load freely throughout the space. This provides a great deal of flexibility, but also requires the operator to actively guide the load. With larger or heavier loads, the force required to guide the load can increase, especially if the load has an irregular shape or if precise positioning is required. Vacuum lifters are particularly well-suited for flat, non-porous materials such as sheets, boxes, and glass panels.
Mobile lift: stable position, less freedom of movement
A mobile lifter operates on a fixed lifting column or arm and lifts the load vertically along a predetermined path. The employee does not have to actively guide the load as much, but also has less freedom of movement. This makes mobile lifters ideal for repetitive, standardized tasks such as loading pallets or moving drums. The effort required is mainly limited to initiating the lifting motion and fine-tuning the position when setting the load down.
When is a lifting aid no longer sufficient to prevent overexertion?
A lifting aid is no longer sufficient when, despite the weight support, the residual effort still leads to repeated strain on muscles, joints, or the musculoskeletal system. This is the case when the assisting force is too high, the working posture remains unfavorable, or the lifting frequency is too high for the employee in question.
Specific situations in which a lifting aid is insufficient:
- The employee must guide the load while reaching extremely far or bending over
- The lifting frequency is so high that even the residual stress causes cumulative stress
- The workstation is so narrow that the employee has to work in unnatural positions despite using the lifting aid
- The lifting aid is not adapted to the weight or shape of the load, which forces the employee to compensate
In such cases, further automation of the process is the appropriate step. Semi-automatic solutions, such as palletizers or integrated rail systems, can further reduce the remaining effort to a minimum and are a logical next step after a basic lifting aid.
How do you choose the right lifting aid for a specific workstation?
Choosing the right lifting aid for a workstation requires an analysis of four factors: the weight and shape of the load, the movement the employee must perform, the frequency of the task, and the available space. No single device is suitable for every situation, and the wrong choice can negate the ergonomic benefits.
A structured selection process involves the following steps:
- Assess the load: weight, dimensions, material, and gripping surface
- Analyze the movement: lifting vertically, moving horizontally, rotating, or a combination
- Determine the frequency: occasionally, regularly, or continuously
- Assess the workspace: height, width, floor type, and presence of obstacles
- Test the solution in practice: a test setup using your own equipment provides the most reliable information
If you are unsure about the right choice, a workstation analysis conducted by a specialist offers the greatest certainty. This prevents the purchase of a lifting aid that does not sufficiently reduce ergonomic strain or that disrupts the workflow.
How Logitrans Handling Helps Reduce Physical Strain in the Workplace
We guide companies from the initial analysis through to the implementation of an ergonomic lifting solution that effectively reduces the physical strain on employees. Our approach is practical and fully tailored to the specific workstation and type of load.
- Free Workstation Analysis: Our specialists analyze the physical demands of the workplace and identify areas where the residual effort is too high
- Wide product range: from vacuum lifters and mobile lifters to palletizers and rail systems, designed for boxes, bags, sheets, pallets, drums, and rolls
- Demonstration Room in Drongen: Test the lifting solution with your own materials before you decide
- Training during installation: Employees learn how to use the lifting aid correctly so that the ergonomic benefits are realized in practice
- Maintenance Contracts: A well-maintained lifting aid maintains its performance and keeps the residual force to a minimum
Would you like to know which lifting aid most effectively reduces the physical strain on your employees at your specific workstation? Contact us for a no-obligation consultation or a free workstation analysis.
Related Articles
- Is it smarter to rent or buy a lifting aid?
- What are the legal requirements regarding manual lifting in the workplace?
- What should I do if employees keep complaining about back pain in the warehouse?
- How often should a lifting aid be maintained, and how much does it cost?
- How do I calculate the ROI of a lifting aid for my executive team?
