Workstation Design Lesson Plan Objectives – The students will be able to explain the basics of anthropometry in workstation design, how to design workstation using guidelines and how analysis tools can also be used to help with work station design. Method - A combination of lecture and group activities using the the PowerPoint presentation as your guide. Activities- There will be three group Activities for this module. Have the workers divide up into groups of three or four for the following activities. -Activity 1-Design a workstation using anthropometry -Activity 2-Design a workstation using guidelines -Activity 3-Analyze a lifting job and then modify it Resources - PowerPoint presentation in both English and Spanish. - Notes for each slide in English discusses the key points that you would expect the student to learn. -Job Strain Index -Video Clip of hand intensive work -WISHA Checklist -WISHA example problem

Tools/Methods of Workstation Design Anthropometry Design Guidelines Design Tools There are several methods available for employees to use to setup workstations. Here are three areas that your workers can use for this purpose.

Anthropometry Measurement of human dimensions Anthropos = human Metrikos = measuring

People Are Different Age Differences Height Differences

Anthropometric Data You will notice that there are dimensions for both males and females. When designing workstations we would like to accommodate a large part of the population. One way to do that is to design workstations to fit workers from very small (5th percentile female) to very large (95th percentile male). Tall people will define clearances and small people will define reaches. The above data is for a person in a standing posture. Some key dimensions to consider are elbow height and eye height. The elbow height dimension can be used to help us determine work surface heights or ranges of heights.

Anthropometric Data Here is similar data for seated people. You could use this data again to determine work surface height and seating dimensions. You could could also use data like knee height to determine clearances for bottom of workstations. Activity One Your company is putting in a new deboning line that will have both male and female workers on the line. If the highest cuts are made at the top of the cone, how would you determine how tall the highest platform height should be and how high the lowest platform should be? What measurements would you use to determine these dimensions? Elbow height would be a good place to start. Range based on this example could be 36.9 to 46.9 inches below the top of the cone.

Using Anthropometric Data Design for the extremes Design for an adjustable range Design for the average?

Design Guidelines Some people have taken the data from anthropometry and other sources and converted them to guidelines that can be used to design work stations. Over the next few slides we will discuss some of these guidelines and some of the principals behind them.

Posture Definitions The students should be reminded of the posture definitions above. In the diagram above it shows several types of postures. The most important concept is the idea of the neutral posture. This is where the body has the least amount of stress. Notice both the hand postures and the arm postures. There are similar drawings to used to define trunk and leg postures.

Affect of Posture on Grip Strength This slide shows some additional affects of posture. Not only are the body parts at least stress in the neutral postures, they are also at their strongest. The pictures above show that when people deviate, flex, or extend their hands and wrists they are not able to exert as much grip force (squeezing a handle like pliers). If work requires a person to work in one of these postures and they have to use tools that require a certain amount of force, it is possible that they will not be able to perform the work due to the reduction in strength that the person is able to apply. You can find similar diagrams for pinch forces.

Acceptable/Unacceptable Work Positions The concept that we are trying to reinforce here is that work needs to be in front of the employee. We need to design tasks in this manner. Reaching behind the body or working with the upper arm raised should be avoided.

Effect of Workstation Design on Posture In this slide you can see the effects of work station design on posture. If this were a task where a person was placing chicken parts in totes or removing products from a conveyor you could see the impact of orientation and height. Totes placed too high can cause poor hand and wrist postures. If it is too high it can also cause poor arm postures as well.

Reach/Work Envelopes These pictures show reaches for employees. The first picture shows the overhead shot of a worker at a work station. It defines acceptable reaches and work zones for people. The next shot shows the side view for a seated person. It shows the acceptable reaches for a person who has to grasp an object. You will notice that both pictures express the reaches in arcs.

Reach/Work Envelopes Here is another diagram that displays reaches of workers standing and sitting. It shows how for this reach would be if the workers reached straight in front, 30 degrees to the right , or 45 degrees to the right. You can find several diagrams with similar information in various textbooks or design handbooks. You can also find design guidelines like this for individuals with special needs like those in in wheelchairs.

Optimal Work Zone Here is another diagram that shows you the ideal work zone on a table or work surface. This is where most work should be done while in a seated posture.

Work Surface Heights These two diagrams show the ranges for work station heights for both seated and standing work. As you will notice the heights vary based on the type of task being performed.

Work Surface Heights Here is another example of work surface height guidelines. You can find these type of guidelines in several textbooks or other references. Activity 2 How tall should you make an offline rework station? It involves some fairly detailed cuts to salvage as much breast meat as possible. If workers are working out of totes, where would you locate them so that they are easy to reach.

What does the worker need to know from this presentation?