Learn how to select the correct ergonomic risk assessment tool for the jobs you are evaluating in your workplace.
Effective and efficient ergonomic risk assessments are a vital piece to the ergonomics puzzle.
The goal of an ergonomic assessment is to determine the level of ergonomic risk for the job you are evaluating. Only by quantifying ergonomic risk factors can you develop a plan to prioritize and implement measureable workplace improvements.
Selecting the Correct Ergonomic Assessment Tool for the Job
Choosing the wrong ergonomic risk assessment tool is like trying to hammer a nail into the wall with a screw driver.
It just doesn’t work. It’s frustrating, time consuming and the quality of your craftsmanship suffers.
That’s why it’s important to choose the right tool. (And then use it correctly, of course. Learn how to use each tool by downloading our step-by-step guides to recommended ergonomic assessment tools. Click here for access. )
The ergonomic assessment tools you put in your tool belt need to be scientifically valid, effective and efficient. For a list of our recommended tools, click here.
Ergonomic Assessment Tool Selection Matrix
Now that you have a few tools in your tool belt, you need to match the tool with the type of job task you are evaluating. Below is a simple matrix we’ve put together to match the type of job task with the corresponding ergonomic assessment tool.
For Lifting/Lowering
WISHA Lifting Calculator
Developed by the Washington State Department of Labor and Industries and based on NIOSH research related to the primary causes of back injuries. This lifting calculator can be used to perform ergonomic risk assessments on a wide variety of manual lifting and lowering tasks, and can be also used as a screening tool to identify lifting tasks which should be analyzed further using the more comprehensive NIOSH Lifting Equation.
NIOSH Lifting Equation
This is a tool frequently used by occupational health and safety professionals for a more comprehensive assessment (when compared to the WA State Lifting Calculator) of manual material handling risks associated with lifting and lowering tasks in the workplace. The primary product of the NIOSH equation is the Recommended Weight Limit (RWL), which defines the maximum acceptable weight (load) that nearly all healthy employees could lift over the course of an 8 hour shift without increasing the risk of musculoskeletal disorders (MSD) to the lower back.
For Pushing, Pulling and Carrying
Snook Tables
The Snook Tables outline design goals for various lifting, lowering, pushing, pulling, and carrying tasks based on research by Dr. Stover Snook and Dr. Vincent Ciriello at the Liberty Mutual Research Institute for Safety. The tables provide weight/force values, for specific types of tasks that are deemed to be acceptable to a defined percentage of the population. This is done by comparing data for each of the specific manual handling tasks against the appropriate table.
For Upper Body Posture
Rapid Upper Limb Assessment (RULA)
This diagnostic tool assesses biomechanical and postural load requirements of job tasks/demands on the neck, trunk and upper extremities. A single page form is used to evaluate required body posture, force, and repetition. Based on the evaluations, scores are entered for each body region in section A for the arm and wrist, and section B for the neck and trunk. After the data for each region is collected and scored, tables on the form are then used to compile the risk factor variables, generating a single score that represents the level of MSD risk.
For Entire Body Posture
Rapid Entire Body Assessment (REBA)
This tool uses a systematic process to evaluate whole body postural MSD and ergonomic design risks associated with job tasks. A single page form is used to evaluate required body posture, forceful exertions, type of movement or action, repetition, and coupling. A score is assigned for each of the following body regions: wrists, forearms, elbows, shoulders, neck, trunk, back, legs and knees. After the data for each region is collected and scored, tables on the form are then used to compile the risk factor variables, generating a single score that represents the level of MSD risk.
For Vibration
Hand-Arm Vibration Calculator
Although NIOSH has not issued a directive related to HAV, the UK developed guidelines under the Control of Vibration at Work Regulations in 2005 using the 2002 EU Physical Agents (Vibration) Directive. This regulation established and introduced vibration exposure action and limit values. In these regulations, the action value was set at a vibration magnitude of 2.5 m/s² and the limit value to 5 m/s². Both values are A(8) values, meaning they are average vibration magnitude values over the course of a 8-hour workday. This regulation serves as a good guide to evaluate HAV exposure, and also offers suggestions with respect to reducing associated risks.
Conclusion
Solving the ergonomics puzzle is difficult, but it can be done. Start by conducting effective and efficient ergonomic assessments, and make sure you’re using the right tool for the job.
For more information on how to use each tool correctly, don’t forget to download our free step-by-step guides to recommended ergonomic assessment tools. Click here for access.
