The importance of an Ergonomics investigation before designing or changing a production system
In this article I will explain why it is important to do an Ergonomics Investigation before we design or redesign a production system.
Every Ergonomic Investigation I have undertaken has saved my client substantially – either capital investment or increased productivity. Ergonomics is one of the most misused words in the English language.
The definition of the discipline of Ergonomic as defined by the International Ergonomics Association (IEA, 2000) is:”Ergonomics is the scientific discipline that deals with understanding the interaction between humans and other elements of a socio-technical system. In this definition, ergonomics is the profession that applies theory, principles, data and design methods to optimize human well-being and the overall performance of a system.”
So now you know!
The most practical application of this science is improving productivity; however the most common motivation for using an “Ergonomist” by management is to improve safety.
One can look at reducing the “lost” production time, thus speeding up the process, or making it easier for people to do their job. It will inevitably be one of these the two first mentioned. Making it safer improves productivity as accidents cause loss in production time. Reducing the chances that operators make mistakes is also a practical application of ergonomics.
The usual way I become involved in a project is by management wishing to solve a problem.[AM1] Often they already have an idea how they want it done, but want affirmation before spending the budget. Let me illustrate this by giving you an example of one of my projects that resulted in saving company about 150K.
The objective was to increase the production output of two sides- by- side operating presses. One press was filled with product while the other one cycled through its pressing process. The way it was set up using both presses at the same time did not result in much more production than using just one press. [AM2]Why this was, was not obvious to management. My investigation method was, talking to the operators of the morning and afternoon shift, observing what they were doing, and making a visual recording in an unobtrusive way. As there were short periods in the process where the operators had to wait for the cycle to finish I had the opportunity to ask lots of questions. This part of the investigation took me about three hours.
Back at the office I looked at my notes and watched to the footage. I had more than an hour’s recordings of a 5 minute process. Watching this footage repeatedly I picked up operational movements things that I had not noticed before.
Another matter that surfaced was that the operators did not want to work both presses at the same time because of the way the auxiliary materials used in the pressing process were presented to the operators. My background in engineering was very helpful to find a workable solution. I drew up [AM3]a proposal for changing the plant layout and some of the methodology.
In the meantime my questioning made the process workers more aware of the problems and they started talking to each other and management about what could be done about them. What my questioning did was making make it clear to operators that a change was going to happen, and as a result, they wanted to be involved with what was going to happen.
My report and floor plan was a catalyst for them to come up with alternative ideas. The result was that the company only spend 50K of the 200K originally budgeted for.
Ergonomics is not rocket science, but a bringing together of lots of different ideas and methods, and measuring what is happening, and predicting what will change when new methodologies are used.
But most importantly (when done correctly) the production workers have the opportunity to be involved in finding a solution they are happy with. Another example was the desire of management to reduce the injury rate of the operators, not to increase the production rate per hour.
This example involves a slaughter house where the animals are gutted skinned and cut in quarters. Management already had looked at equipment in other slaughter houses and were prepared to spend up to $225K to have this installed in their plant.
However the size of the equipment and the building meant this was never going to fit and resource consent was needed to change the height of the building.
The budget and timeframe did not allow for this approach. We already had an idea in our mind what we could do, but a visit to the plant was needed to get some more details. Our arrival and asking management and the operator’s questions prompted a discussion among them and they came up with a totally different approach.
They did a trial right there and then and this proved to be feasible. However some equipment needed to be built for this. We made a visual recording, took notes and some measurements.
We used this to produce a 3D “mock-up” drawing of the equipment positioned in the building. Our proposal was fine-tuned, detailed drawings made, and discussed with the client. Our quote was accepted by the client saving them about 125 K. In both occasions the investigation and cooperation with the operators combined with our engineering experience produced a great result.
– Aaldert Verplanke www.mandesign.co.nz